Various guides to writing for Medicine and to scientific writing in general are available at classmark AA6c in the Medical Library.
There is no single way of writing references, however you should cite references in a consistent style. Biomedical journals mostly use either the Harvard or Vancouver formats for citing references.
The Vancouver Group - now known as the International Committee of Medical Journal Editors - first published its Uniform Requirements for Manuscripts Submitted to Biomedical Journals in 1979. The current version of Uniform requirements for Manuscripts Submitted to Biomedical Journals is available online. For samples of reference citation formats, consult the National Library of Medicine.
There are many guides to the Harvard style of referencing available on the web, for example at Nottingham Trent University or University of Sussex.
Other useful resources include:
The Journal title abbreviations in Medicine page gives advice on how you can ascertain journal title abbreviations to be used in your reference list.
The Library's Plagiarism: information and advice for students page offers guidance on plagiarism and includes these sections: