This site offers guidance for determining and negotiating authorship status between multiple authors. There are several resources linked here for guidance related to order of authors, authorship requirements, etc.
This agreement posted by the APA Science Student Council determines author and outlines the publication of the project between faculty supervisors and students. It can be adapted for faculty use.
The authors of this 2015 article from Western Journal of Nursing Research outlines strategies for managing co-authorship experiences. Authors from many nursing research institutions contribute their perspectives and advice about working in teams to publish.
The authors of this Journal of Professional Nursing article (1997) offer "recommendations to reduce problems that may arise . . . because of authorship issues." Sample guidelines and blueprints for prospective coauthors and project team members.
This 2014 article from Elsevier's Biological Conservation journal addresses frequently encountered issues (by the publisher and editors) involving problematic co-author issues. A sample agreement for co-authors who publish in scientific literature is included as a template for co-author teams to plan for publishing together.