American Society of Microbiology (ASM) Style

American Society of Microbiology (ASM) uses a citation-sequence system.

• List sources on a references page in the order in which you refer to them in your paper, and number them sequentially.
• Cite each source by indicating its number in parentheses in your text.
• For example, the first source you mention or quote should be cited in the text of your paper with the numeral 1 in parentheses (1).
  • Note: If the citation comes at the end of a sentence, the period should follow the parentheses that enclose the citation number.
• The full citation for that source should appear in a list of references at the end of your paper.
• ASM style does not use hanging indents in the references list.

References cited in the text, but not listed in the references section

These references should be made parenthetically in the text but should not be included in the reference list.

Unpublished data/Manuscripts

...(Author's first initial(s). Author's last name, unpublished data/manuscript/document).

• …similar results (R.B. Layton and C.C. Weathers, unpublished data).

Other unpublished materials (posters, handout, lab instructions)

...(Author's first initial(s). Author's last name, Affiliated institution/organization/conference, Location [if relevant], Date [DMY]).

• ...when the agent operates as described previously (M.G. Gordon and F.L. Rattner, presented at the Fourth Symposium on Food Microbiology, Overton, IL, 13 June 1989).
• ...according to directions (A. Professor, Biology Lab Powerpoint, Piedmont Virginia Community College, 15 March 2015).

Websites

...(http://url).

• …as suggested by the World Health Organization (URL).
  • URLs for companies that produce any of the products mentioned in your study or for products being sold may not be included in the article. However, company URLs that permit access to scientific data related to the study or to shareware used in the study are permitted.

Types of references listed in the references section

• journal articles (print, online, and in press*)
• books and book chapters (print, online, and in press*)
• patents
• theses and dissertations
• published conference proceedings
• meeting abstracts from published abstract books or journal supplements
• letters to the editor
• company publications

*A reference to an in-press ASM publication should state the control number (e.g., JCM00577-13) if it is a journal article or the name of the publication if it is a book. 

Note on authors

• ASM does not permit the use of the abbreviation et al. for second and subsequent authors; references must include the names of all authors, no matter how many for in-text and full reference citations. 

Note on journal titles

• In references to material published in journals, the journal title must be abbreviated according to standard practice. Appropriate journal title abbreviations can be found in the PubMed Journal Database (URL: http://www.ncbi.nlm.nih.gov/nlmcatalog/journals). 

Note on DOIs

• DOIs are not needed for most references.
• URLs for government reports and other references not indexed should be provided.

Print journal article

Author's last name Author's first initial(s). Year published. Title of article. Journal abbreviation Volume number(Issue number):page numbers.

• Caserta E, Haemig HAH, Manias DA, Tomsic J, Grundy FJ, Henkin TM, Dunny GM. 2012. In vivo and in vitro analyses of regulation of the pheromone-responsive prgQ promoter by the PrgX pheromone receptor protein. J. Bacteriol. 194:3386-3394.

Online journal articles

Author's last name Author's first initial(s). Year published, posted, or revised. Title of article. Journal abbreviation Volume number(Issue number):page numbers. doi.

• Winnick S, Lucas DO, Hartman AL, Toll D. 2005. How do you improve compliance? Pediatrics 115:e718- e724.
• Smith FX, Merianos HJ, Brunger AT, Engelman DM. 2001. Polar residues drive association of polyleucine transmembrane helices. Proc. Natl. Acad. Sci. U.S.A. 98:2250-2255. doi:10.1073/pnas.041593698.

References to material published online must provide essentially the same information contained in references to printed material.

• For online journal articles, posting or revision dates may replace the year of publication; a DOI (preferred) or URL is required for articles with nontraditional page numbers or electronic article identifiers.

Article/chapter in print book

Author's last name Author's first initial(s). Year published. Title of chapter, page numbers. In Editor's last name Editor's first initial(s) (ed), Title of work, edition (if relevant), volume number (if relevant). Publisher, Location of publication.

• Forman MS, Valsamakis A. 2011. Specimen collection, transport, and processing: virology, p 1276-1288. In Versalovic J, Carroll KC, Jorgensen JH, Funke G, Landry ML, Warnock DW(ed), Manual of clinical microbiology, 10th ed, vol 2. ASM Press, Washington, DC.

Article in press

Author's last name Author's first initial(s). Article title (optional)/control number. Journal title abbreviation, in press.

• Cox CS, Brown BR, Smith JC. J. Gen Genet, JCM00589-43. J. Bacteriol. “in press.”
  • Article title is optional; journal title is mandatory.
  • A reference to an in-press ASM publication should state the control number if it is a journal article or the name of the publication, if it is a book.

Print book

Author's last name Author's first initial(s). Year published. Title of book, edition (if relevant). Publisher, Location of publication.

• Sambrook J. 1989. Molecular cloning: a laboratory manual, 2nd ed. Cold Spring Harbor Laboratory, Cold Spring Harbor, NY.

Online book

Author's last name Author's first initial(s). Date published (DMY), posting date. Chapter number, Chapter title. In Editor's last name Editor's first initial(s) (ed), Title of Work. Publisher, Location of publication. doi (if applicable).

• Gregory 2 September 2009, posting date. Chapter 2.5.4, Structural basis for the decoding mechanism. In Böck A, et al (ed), EcoSal—Escherichia coli and Salmonella: cellular and molecular biology. ASM Press, Washington, DC. doi:10.1128/ecosal.2.5.4.
  • Note that each chapter has its own posting

Book in press

Author/s (Last Name First Initial). In Author/s (Last name First initial), Book title (Sentence case), in press. Publisher, Location Publisher.

• Fitzgerald G, Shaw D. In Waters AE (ed), Clinical microbiology, in press. EFH Publishing Co., Boston, MA.
  • Chapter title is optional.
  • A reference to an in-press ASM publication should state the control number if it is a journal article or the name of the publication if it is a book.

Conference proceedings

Author last name Author first initial(s). Year. Abstract or presentation title (optional), page number(s). Title of conference proceedings. Name of organization, Location of conference.

• Carlson E. 2013. Selective penicillin-binding protein imaging probes reveal substructure in bacterial cell division, p 59. Final Program 113th Gen Meet Am Soc Microbiol. American Society for Microbiology, Washington, DC.

Company publication

Author. Year published. Title of publication. Corporation, Location of corporation.

• 2006. Yeast DNA isolation system: instruction manual. Stratagene, La Jolla, CA.
  • Use the company name as the author if none is provided for a company publication.

Thesis/dissertation

Author's last name Author's first initial(s). Year published. Title of thesis/dissertation (optional). Ph.D. thesis/dissertation. Affiliated University, Location.

• O'Malley DR. 1998. My time as a graduate student. Ph.D. thesis. University of California, Los Angeles, CA.
  • Title is optional.

Formatting

ASM Format Checklist

• Double-space all text, including references and figure legends.
• Font no smaller than 12 point and clear to read.
• Number pages bottom right.
• All lines should be numbers in a continuous format.
• Provide accession numbers for all newly published chemical sequences.
• Provide references for accession numbers and code (with URLs).
• Confirm the genetic and chemical nomenclature conforms to instructions: jcm.asm.org
• ASM style does not use hanging indents in the references list.

Headings and subheadings

LEVEL 1 HEAD (Flush left, all caps, boldface)

Level 2 Head (flush left, title capitalization, boldface)

            Level 3 head. (boldface paragraph lead-in, sentence capitalization)

            (i) Level 4 head. (boldface subparagraph lead-in, sentence capitalization)

            (a) Level 5 head. (lightface italic sub-subparagraph lead-in, sentence capitalization

Additional information can be found at https://asm.org/

References

American Society for Microbiology (2021). Instructions to authors. Retrieved from https://jcm.asm.org/content/scope.

Piedmont Virginia Community College (2021). https://libguides.pvcc.edu/citationstyles/asm-books