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

Retallack, G.J. A 300-Million-Year Record of Atmospheric Carbon Dioxide from Fossil Plant Cuticles. Nature 2001, 411, 287–290.

A journal article with 2 authors

Schultz, R.M.; Williams, C.J. The Science of ART. Science 2002, 296, 2188–2190.

A journal article with 3 authors

Sander, R.; Crutzen, P.J.; von Glasow, R. Comment on “Reactions at Interfaces as a Source of Sulfate Formation in Sea-Salt Particles” (II). Science 2004, 303, 628; author reply 628.

A journal article with 4 or more authors

Johnston, D.T.; Wing, B.A.; Farquhar, J.; Kaufman, A.J.; Strauss, H.; Lyons, T.W.; Kah, L.C.; Canfield, D.E. Active Microbial Sulfur Disproportionation in the Mesoproterozoic. Science 2005, 310, 1477–1479.

Books and book chapters

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

An authored book

Rowlinson, M. A Practical Guide to the NEC3 Engineering and Construction Contract; Wiley-Blackwell: Oxford, UK, 2010; ISBN 9781444340181.

An edited book

Complex Networks VI: Proceedings of the 6th Workshop on Complex Networks CompleNet 2015; Mangioni, G., Simini, F., Uzzo, S.M., Wang, D., Eds.; Studies in Computational Intelligence; Springer International Publishing: Cham, 2015; Vol. 597; ISBN 9783319161112.

A chapter in an edited book

Yorke, J.; Vidovich, L. Research Methods. In Learning Standards and the Assessment of Quality in Higher Education: Contested Policy Trajectories; Vidovich, L., Ed.; Springer International Publishing: Cham, 2016; pp. 89–109 ISBN 9783319329239.

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

Andrew, E. Why Do Only Some People Get ‘Skin Orgasms’ From Listening To Music? Available online: https://www.iflscience.com/plants-and-animals/why-do-only-some-people-get-skin-orgasms-listening-music/ (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 Controls Over Computer-Generated Output at the Naval Supply Center, Oakland; U.S. Government Printing Office: Washington, DC, 1970;

Theses and dissertations

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

Doctoral dissertation

Powell, F.M. A Study of the Effects of Nanoparticle Modification on the Thermal, Mechanical and Hygrothermal Performance of Carbon/Vinyl Ester Composites. Doctoral dissertation, Florida Atlantic University: Boca Raton, FL, 2012.

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

Kelly, S.R. Good Neighbors, Bad Border. New York Times 2012, A31.

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