How to format your references using the Challenges citation style

This is a short guide how to format citations and the bibliography in a manuscript for Challenges. For a complete guide how to prepare your manuscript refer to the journal's instructions to authors.

Using reference management software

Typically you don't format your citations and bibliography by hand. The easiest way is to use a reference manager:

Paperpile	The citation style is built in and you can choose it in Settings > Citation Style or Paperpile > Citation Style in Google Docs.
EndNote	Find the style here: output styles overview
Mendeley, Zotero, Papers, and others	The style is either built in or you can download a CSL file that is supported by most references management programs.
BibTeX	BibTeX syles are usually part of a LaTeX template. Check the instructions to authors if the publisher offers a LaTeX template for this journal.

Journal articles

Those examples are references to articles in scholarly journals and how they are supposed to appear in your bibliography.

Not all journals organize their published articles in volumes and issues, so these fields are optional. Some electronic journals do not provide a page range, but instead list an article identifier. In a case like this it's safe to use the article identifier instead of the page range.

A journal article with 1 author

Haigwood, N.L. HIV: Tied down by Its Own Receptor. Nature 2015, 519, 36–37.

A journal article with 2 authors

Pedraza, J.M.; Paulsson, J. Effects of Molecular Memory and Bursting on Fluctuations in Gene Expression. Science 2008, 319, 339–343.

A journal article with 3 authors

Maiorano, D.; Moreau, J.; Méchali, M. XCDT1 Is Required for the Assembly of Pre-Replicative Complexes in Xenopus Laevis. Nature 2000, 404, 622–625.

A journal article with 4 or more authors

Norell, M.; Ji, Q.; Gao, K.; Yuan, C.; Zhao, Y.; Wang, L. Palaeontology: “modern” Feathers on a Non-Avian Dinosaur. Nature 2002, 416, 36–37.

Books and book chapters

Here are examples of references for authored and edited books as well as book chapters.

An authored book

Basener, W.F. Topology and Its Applications; John Wiley & Sons, Inc.: Hoboken, NJ, 2006; ISBN 9780470067949.

An edited book

Bioluminescence: Fundamentals and Applications in Biotechnology - Volume 1; Thouand, G., Marks, R., Eds.; Advances in Biochemical Engineering/Biotechnology; Springer: Berlin, Heidelberg, 2014; Vol. 144; ISBN 9783662433843.

A chapter in an edited book

Jankowski, D.; Jackowski, K. Evolutionary Algorithm for Decision Tree Induction. In Computer Information Systems and Industrial Management: 13th IFIP TC8 International Conference, CISIM 2014, Ho Chi Minh City, Vietnam, November 5-7, 2014. Proceedings; Saeed, K., Snášel, V., Eds.; Lecture Notes in Computer Science; Springer: Berlin, Heidelberg, 2014; pp. 23–32 ISBN 9783662452363.

Web sites

Sometimes references to web sites should appear directly in the text rather than in the bibliography. Refer to the Instructions to authors for Challenges.

Blog post

O`Callaghan, J. These Are Some Of Rosetta’s Last Stunning Images Of Comet 67P Available online: https://www.iflscience.com/space/rosettas-last-images-of-comet-67p/ (accessed on 30 October 2018).

Reports

This example shows the general structure used for government reports, technical reports, and scientific reports. If you can't locate the report number then it might be better to cite the report as a book. For reports it is usually not individual people that are credited as authors, but a governmental department or agency like "U. S. Food and Drug Administration" or "National Cancer Institute".

Government report

Government Accountability Office U.S.-Korea Fighter Coproduction Program; U.S. Government Printing Office: Washington, DC, 1990;

Theses and dissertations

Theses including Ph.D. dissertations, Master's theses or Bachelor theses follow the basic format outlined below.

Doctoral dissertation

Watson, D.J. How the Lead Systems Integrator Experience Should Enhance Efforts to Rebuild the Defense Acquisition Workforce. Doctoral dissertation, George Washington University: Washington, DC, 2010.

News paper articles

Unlike scholarly journals, news papers do not usually have a volume and issue number. Instead, the full date and page number is required for a correct reference.

New York Times article

Sophia Kishkovsky; Compiled by Arts, Briefly; 2 Missing Russian Works Recovered. New York Times 2006, B8.

In-text citations

References should be cited in the text by sequential numbers in square brackets:

This sentence cites one reference [1].
This sentence cites two references [1,2].
This sentence cites four references [1–4].

About the journal

Full journal title	Challenges
ISSN (online)	2078-1547
Scope