AAS Journal Reference Instructions

The reference and bibliographic style of the AAS Journals generally requires that references should be cited in the text by the last name of the authors(s) and the date of publication, with no comma before the date, according to these examples: articles by three or more authors are cited by the first author followed by “et al.” and the date (A.A. Goodman et al. 2003); articles by two authors are cited by both last names joined by an ampersand (G.B. Press & W.H. Rybicki 1992); and articles by a single author are cited by the last name and the date of publication (G.E. Hale 1929).

The AAS Journal’s BibTeX style file encodes these reference styles and is provided with our latest AASTeX release (Version 6+). Detailed LaTeX instructions may be found in the AASTeX Guide.

Citation Policies

Dataset Citations

The most critical element of data citation is the citation of the specific source of a dataset used in a new manuscript and the citation of that data’s reference publication as required by the data creator’s. By specific source of the data, we mean that if data is available from many sources, the one that must be cited is the one that was used to obtain the data. By reference publication, we mean that journal article (or other technical document) that describes the dataset used and is specified by the creators of a dataset as the preferred citation. We provide below a series of templates to highlight the various types of relationships that exist between reference publications and specific sources of data.

AAS Journal Table citation

The AAS Journals now provide individual dataset DOIs and a dataset landing page for articles with online-only content. In this citation example, an author is reusing the machine-readable table that has a dataset DOI in the published article. The resulting text gives attribution to the data creators by citing the reference publication (journal article) and gives precise information about the source of the data used, leading the reader directly to that data via the dataset citation.

We used CO (1-0) rovibrational line fluxes published by D.A. Dickson-Vandervelde et al. (2025a) in the original machine-readable format (D.A. Dickson-Vandervelde et al. 2025b, Table 2).

In LaTeX, using ADS bibcodes or dataset DOIs as reference keys

We used CO (1-0) rovibrational line fluxes published by \citet{2025AJ….170..130D} in the original machine-readable format \citep[][, Table 2]{doi:10.3847/1538-3881/ade80e/data2}.

If a Table does not have a dataset DOI, e.g., because it does not have an online-only component or because that online-only component does not have a DOI, then best practice is to mention simply the Table by number:

We used the joint fit for WASP-130 published by \citet{2025AJ….170…70E} (their Table 6).

 

AAS Journal Online Figure citation

In this example, the author is referring to one of a specific set of online-only Figures previously published in the AAS Journals. The set has a DOI, and can be cited in bulk. The specific element of the set must be provided in free text.

This geometry is clearly suggested by the self-absorbed CO emission of CW Tau (D.A. Dickson-Vandervelde et al. 2025a; their online Figure 6.6, Dickson-Vandervelde et al. 2025c).

In LaTeX, using ADS bibcodes and component DOIs as reference keys:

This geometry is clearly suggested by the self-absorbed $^{12}$CO emission of CW Tau (\citealias{2025AJ….170..130D}; their online Figure 6.6, \citealias{oi:10.3847/1538-3881/ade80e/data3}).

 

Citing the Vizier version of a Table published in the AAS Journals

In this example, a data table originally published in the AAS journals has been ingested and hosted by the Vizier service at the Strasbourg astronomical Data Center. Tables ingested into Vizier are significantly more interoperable than the version hosted in the Journals, including enabling the data to be used directly in the Virtual Observatory and by Python tools such as astroquery.  As before, the goals of a data citation are to attribute first the creators of the data and, second, to give precise information about the source of the data used, leading the reader directly to that data via the dataset citation.

It is not relevant whether or not the original Table had a dataset DOI from the Journal article. An author in this case is referring specifically to that version of the data hosted by Vizier. The Vizier version of the data may or may not match the original table. All AAS journal data hosted by Vizier has a Vizier-assigned DOI, which should be used for making the citation:

We used the catalog TESS-based short-period variables published by G. Olmschenk et al. (2024) as provided by Vizier (G. Olmschenk et al. 2025).

In LaTeX, using ADS bibcodes and component DOIs as reference keys:

We used the catalog TESS-based short-period variables published by \citet{2024AJ….168…83O} as provided by Vizier \citep{doi: 10.26093/cds/vizier.51680083}.

Citing data on Zenodo

We include this example because authors are increasingly hosting large or unique datasets on third-party repositories, such as Zenodo.

The AAS Journals support data sharing in all venues, and we provide a workflow that allows us to assist and curate such Zenodo-based data publications. When posting data to services such as Zenodo, please review the repository best practices in our Data Guide and consider submitting unpublished data for review by our Data Editor Team via the AAS Journal’s Zenodo community.

Again, the principle focus is the citing of both the reference journal article and the corresponding dataset publications:

M. S. Marley et al (2021a) present the cloudless, rainout chemical equilibrium models “Sonora Bobcat”; we made use of these models as published on Zenodo (M. S. Marley et al 2021b).

In LaTeX, using ADS bibcodes and Zenodo DOIs as reference keys:

\citet{2021ApJ…920…85M} present the cloudless, rainout chemical equilibrium models “Sonora Bobcat”; we made use of these models as published on Zenodo \citep{doi:10.5281/zenodo.5063476}.

Citing data hosted in NASA archives

These examples highlight the practice of citing datasets obtained from high-level science products hosted by NASA archives such as the Barbara A. Mikulski Archive for Space Telescopes (MAST) and IPAC.

Software Citations

As described in the AAS Journal’s software policy (2016), software can be cited in two ways:

Ideally, both forms of citation should be included; alongside these formal references, authors may also want to include URLs to appropriate code repositories, such as GitHub, as footnotes. Sources of software citations include NASA ADS and metadata indices, such as the Astrophysics Source Code Library. We provide this template for citing both a journal article and the direct software citation, which could be used for other software, as based on the tardis documentation:

We modeled the spectrum of SN 2026qqq using the TARDIS code (W. E. Kerzendorf & S. A. Sim 2014), 
release v2024.10.14 (W. Kerzendorf et al. 2024).

or in LaTeX, assuming the use of the newest aasjournal BibTeX style file:

We modeled the spectrum of SN 2026qqq using the TARDIS code \citep{https://doi.org/10.1093/mnras/stu055}, 
release v2024.10.14 \citep{https://doi.org/10.5281/zenodo.13929578}.

Authors may also include a section below the acknowledgments listing scientific software packages used as part of the work presented in the manuscript. This should be done via the \software AASTeX macro. The content of the command should take the form of a list of software by name with the preferred citation in parentheses, which must also appear in the article’s reference list. For example:

\software{Astropy \citep{https://doi.org/10.1051/0004-6361/201322068, 
               https://doi.org/10.3847/1538-3881/aabc4f, 
               https://doi.org/10.3847/1538-4357/ac7c74},
          Matplotlib \citep{http://dx.doi.org/10.1109/MCSE.2007.55}}

This is analogous to acknowledging a major facility or instrument and is done for the same reason, to give credit to a project which is generally useful for the community. More information can be found in the AASTeX documentation.

Other Online Sources

Electronic catalogs, databases, observers’ guides, instrument documentation, electronic conference proceedings, electronic journals, and other stable (non-changing) documents available online should be listed in the reference list in the same manner as other references. Such sources should be cited by their digital object identifier (DOI) if available. Otherwise, such online sources should give the author(s) or authoring agency, title of the document, location and name of the hosting organization (e.g., Pasadena, CA: JPL), the specific version consulted if any or, alternatively, the last date of access, a page or document number if any, and the URL or persistent identifier (see examples below). References in this class include databases, manuals, conference proceedings, and similar documents. It does not include general informational sites for instruments or projects or articles posted on personal web pages.

If software is used and there is no reference other than a website for downloading computer code, authors should directly cite the codebase, e.g., GitHub, including the same metadata listed above for any other URL. See below for examples.

Unless otherwise required by a resource, URLs for all other electronic resources that lack a sufficient degree of permanence, such as personal web pages, general informational sites for organizations, telescopes, surveys, projects, proposals, and other sites with content that changes regularly, should be given in a footnote at first mention in the text along with the date last accessed, but not listed in the reference list.

Unpublished Material

References to articles in preparation or other sources generally not available to readers should be avoided if possible.

If no publication of record is available, preprints may be listed in the reference list with the version given. Please check preprint references carefully in case any of these have been formally published since your manuscript was prepared; if a preprint has not been formally published, please give the reference (e.g, arXiv) number and the journal to which the work has been submitted.

Private communications, unpublished works, and articles in preparation should be cited only in the run of text, giving authors’ initials and the year if completion is imminent, that is F. Carlon et al. (2009, in preparation).

Reference List Style

Format

All sources cited in the text and tables, including in online-only tables or other data, must appear in the reference list at the end of the manuscript, and all entries in the reference list must be cited in the manuscript.

Reference entries should be ordered alphabetically, starting with the last name of the first author, followed by the first author’s initial(s), and so on for each additional author. For articles with more than five authors, the last name and initials of the first three authors only should be listed, followed by a comma and “et al.” References listed as “et al.” are grouped together and last, as if the fourth author started with “z”; they are not alphabetized by the name of the actual fourth author. Multiple entries for one author or one group of authors should be ordered chronologically, and multiple entries for the same year should be distinguished by appending sequential lower-case letters to the year, even if the author groups are not identical: e.g., Smith, E., Rowe, T., & Jones, A. B. 1999a; Smith, A. B., Thomas, J. R., & Peebles, P. J. E. 1999b; Smith et al. 1999c.

Except in rare instances (e.g., Icarus) ADS bibliographic codes on the ADS site should be used for the appropriate refereed journal abbreviations. A list of codes for non-refereed publications is also available and should be followed.

References should include digital object identifiers (DOI) if available. DOIs should be written in full with either a “doi:” or an “https://doi.org/” prefix, but not otherwise obfuscated by other types of anchor links.

The AAS Journal’s latest BibTeX style file that encodes these reference styles and is provided with our latest AASTeX release.  In most cases BibTeX provided by NASA ADS yields correct reference strings, although some reference managers are known to obliterate high-quality ADS BibTeX.  Detailed LaTeX instructions may be found in the AASTeX Guide.

Repositories

Content related to published articles should be archived in persistent repositories and linked to the article through a digital object identifier (DOI). In addition to software or data published in DOI repositories, our Data Guide details the types of related content that should be archived and linked to the final article through first class references in the bibliography.

The newest AASTeX BibTeX style file supports the current reference list style for digital software or data objects in persistent (“DOI”) repositories as follows:

{author*} {year}, {title}, {version^}, {publisher|howpublished~}, {prefix}:{identifier#}

To illustrate and document this format, we use a corresponding BibTeX entry taken and modified from a real software publication from the Journals. Note that all software/data BibTeX entries should be of the @misctype, but that BibTeX types of @software and @dataset translate directly and correctly to our @misc reference style even if these types are not formally defined in our style file.

                    @misc{lia_corrales_2015_15991,
      author = {Lia Corrales},
      title = {{dust: Calculate the intensity of dust scattering halos in the X-ray}},
      month = mar,
      year = 2015,
      doi = {10.5281/zenodo.15991},
      version = {v1.0},
      publisher = {Zenodo},
      url = {http://dx.doi.org/10.5281/zenodo.15991}
      }

The corresponding reference list entry built with aasjournal+.bst would look like:

Corrales, L. 2015, dust: Calculate the intensity of dust scattering halos in the X-ray, v1.0, Zenodo, doi:10.5281/zenodo.15991

Proofing

Authors will be queried for missing, incomplete, or incorrect information in the reference list.  In most cases BibTeX provided by NASA ADS, in combination with the AAS journal bibtex style, yields correct reference strings. See also the Tips and Tricks for special cases and common problems with BibTeX.

It is especially important that authors recheck reference lists after each revision of the text, to be certain that all references cited in the text are in the reference list, and all references given in the reference list are cited. It is worth stating that using BibTeX solves this problem entirely.

Authors should also check preprint listings, such as arXiv postings, to see if the preprint has been published, or submitted for publication, since the initial preparation of the manuscript.

Examples

Examples are given here of some of the most common citation formats. Except in rare instances (e.g., Icarus) ADS bibliographic codes on the ADS site should be used for the appropriate refereed journal abbreviations. A list of codes for non-refereed publications is also available and should be followed.

If an entry on this page has the title given in the example reference string, then that title is required for this type of reference for all AAS journals.  For the Planetary Science Journal, authors can provide title strings for all references, including journal articles and preprints.

Journal Article

  • Martín, E. L., Rebolo, R., & Zapatero Osorio, M. R. 1996, ApJ, 469, 706, doi:10.1086/177817
  • Aguirre, J. E., Ginsburg, A. G., Dunham, M. K., et al. 2011, ApJS, 192, 4, doi:10.1088/0067-0049/192/1/4

Journal Article in The Planetary Science Journal

  • Lovett, E., Schmidt, C., & Lierle, P. 2025, Europa’s Sodium and Potassium Exosphere during Juno’s Flyby, PSJ, 6, 178, doi:10.3847/PSJ/adeb52
  • Trumbo, S. K., Becker, T. M., Brown, M. E., et al. 2022, A New UV Spectral Feature on Europa: Confirmation of NaCl in Leading-hemisphere Chaos Terrain, PSJ, 3, 27, doi:10.3847/PSJ/ac4580

Software and Dataset Citations

  • Corrales, L. 2015, dust: Calculate the intensity of dust scattering halos in the X-ray, v1.0, Zenodo, doi:10.5281/zenodo.15991
  • NASA Exoplanet Science Institute. (2020). Planetary Systems Table, Last Accessed: 2025-08-17T16:51:09+0000, IPAC. doi:10.26133/NEA12

Software and citable data objects in persistent repositories should include the repository name in addition to the DOI, and the version as appropriate.

Book

  • Donat, W., III, & Boksenberg, A. J. 1993, The Astronomical Almanac for the Year 1994, Vol. 2 (2nd ed.; Washington, DC: GPO)

Where specific pages of a book are cited, these should be given at the text citation, not in the reference list.

Article or Chapter in an Edited Collection

  • Huchra, J. P. 1986, in Inner Space/Outer Space, ed. E. W. Kolb et al. (Chicago, IL: Univ. Chicago Press), 65

Conference Proceedings

  • Salpeter, E. E., & Wasserman, I. M. 1993, ASPC 36, Planets around Pulsars, ed. J. A. Phillips, S. E. Thorsett, & S. R. Kulkarni (San Francisco, CA: ASP), 345

Electronic Conference Proceedings (published only online)

Star Catalogs

  • Hoffleit, D. 1982, The Bright Star Catalogue (New Haven, CT: Yale Univ. Obs.)

Electronic Newsletters (published only online)

Instrument Documentation

  • Gussenhoven, M. S., Mullen, E. G., & Sagalyn, R. C. 1985, CRRES/SPACERAD Instrument Description, Document AFGL-TR-85-0017 (Hanscom, MA: Air Force Geophys. Lab.)
  • Spitzer Science Center. 2004, Spitzer Observers’ Manual (Pasadena, CA: SSC), http://sirtf.caltech.edu/

Preprints

  • Crida, A., Baruteau, C., Gonzalez, J.-F., et al. 2025, arXiv e-prints, arXiv:2508.07859, doi: 10.48550/arXiv.2508.07859
  • Tobin, J. J., et al. 2015, arXiv: 1501.03172, AJ in press
  • Lockwood, G. W., & Skiff, B. A. 1988, Air Force Geophys. Lab. preprint (AFGL-TR-88-0221)

References to preprints are acceptable only for manuscripts not yet published. Please check the arXiv references in case any of these have been formally published since the manuscript was prepared; if the preprints have not been published, please give the arXiv reference number and the journal to which the work has been submitted or is currently in press.

Manuscripts Submitted or In Press

  • Wolk, S. J., & Walter, F. M. 1999, AJ, submitted
  • Wolk, S. J., & Walter, F. M. 1999, AJ, in press

“Submitted” should be used for manuscripts not yet accepted for publication, and “in press” for manuscripts accepted but not yet published. Other unpublished manuscripts must not be listed int he reference list.

BibTeX Tips and Tricks

You can quickly get a BibTeX entry for any DOI, e.g., one issued by a third-party software or data repositories, with a number of websites, e.g., doi2bib.org and citation.doi.org, or with this simple command line call:

curl -LH "Accept: application/x-bibtex" https://doi.org/10.5555/12345678

In addition, any DataCite DOI has a human readable metadata page that is accessible through the URL:  https://commons.datacite.org/doi.org/<doi>, e.g., https://commons.datacite.org/doi.org/10.5281/zenodo.15991. From here you can download the reference in RIS or BibTeX formats.

If you are using BibTeX entry from sources other than SAO/NASA Astrophysics Data System then you should consider the following tips or advice about software/data BibTeX fields and how they translate to a reference in an AAS Journal article:

{author*}
The author field should be formatted to match journal style: last name, first initial, etc.  If the first author is an organizational author, e.g., “Astropy Collaboration” or “Rubin Observatory Science Pipelines Developers”, then you must protect the entire organizational name in curly braces, e.g.,

author = {{Rubin Observatory Science Pipelines Developers}},

Similarly, if you must cite a website or codebase where attribution for the material cannot be ascertained, then a generic creator is an acceptable alternative:

title = {bobolink/exodisolver},
author = {{ExoDisolver developers}},
version = {commit: c46aade96877acba3f3deb4848b0d5faed83edc8},
publisher = {GitHub},
url = {https://github.com/bobolink/exodisolver}

{version^}
Most BibTeX style files, including the older apj.bst, do not pick up the {version} BibTeX key, or it may not be included in the BibTeX you download. You many have to insert it manually into your final reference. The newest aasjournal+.bst style file does read and format the version tag. The version tag can also be used to document a variety of version-related information, including:

if the resource has a single URL or DOI and provides a specific date of last revision in place of a formal version string:

version = {Last updated: YYYY-MM-DD},

if the resource is changing daily or weekly without providing an update date:

version = {Last Accessed: YYYY-MM-DD HH:MM},

if you are citing a specific commit for software that you used:

version = {Commit: c46aade96877acba3f3deb4848b0d5faed83edc8},

{publisher|howpublished~}
Please use the {publisher} key; you may have to add it manually as some repositories do not by default provide BibTeX with this key entered. Note you can “trick” BibTeX to use the {howpublished} key for the publisher and avoid manually fixing things, but this is not recommended. The new aasjournal+.bst style file can correctly parse the {publisher} BibTeX key. Note: the publisher is the entity responsible for hosting or providing the resource. It is not, e.g., the institution of the creators.

{prefix}:{identifier#}
While in the majority of cases the “prefix” of the data/code persistent identifier will be a “doi”, we reserve the generic model for edge cases, including “hdl”, “arXiv”, “ark”, “purl”, “ivoa”, “abs”, etc.