Our reference style requirements are in accordance with the Uniform Requirements for Manuscripts Submitted to Biomedical Journals by the ICMJE. The references should be numbered in the order in which they appear in the text. In the text, tables, and legends, identify references using Arabic numerals in brackets.
Note: List all authors when they are six or fewer; when they are seven or more, list the first six, followed by “et al”

Samples:
- Articles in journals
Shirzad H, Abbasi Farajzadeh M, Hosseini Zijoud SR. The Role of Military and Police Forces in Crisis Management due to the COVID-19 Outbreak in Iran and the World. Journal of Police Medicine. 2020;9(2):63-70.
-  Articles in journals with more than six authors
Kheirandish P, Seyedalinaghi SA, Hosseini M, Jahani MR, Shirzad H, Foroughi M, et al. Prevalence and correlates of HIV infection among male injection drug users in detention in Tehran, Iran. JAIDS Journal of Acquired Immune Deficiency Syndromes. 2010;53(2):273-5..
-  Article In press
Kheirandish P, Seyedalinaghi SA, Hosseini M, Jahani MR, Shirzad H, Foroughi M, et al. Prevalence and correlates of HIV infection among male injection drug users in detention in Tehran, Iran. JAIDS Journal of Acquired Immune Deficiency Syndromes. 2010. [In press].
- Article In other language
Zaboli R, Hasani M, Khalagi K, Shirzad H. The relationship between patient's safety culture and patients' perception of healthcare quality in military hospitals in 2013. Journal of police medicine. 2014;3(1):19-30. [Persian].
-  Books and other monographs
Marx JA, Hockberger RS, Walls RM, Adams GA. Rosen's emergency medicine: concepts and clinical practice. 6th ed. Philadelphia: Mosby Incorporated; 2010. p. 1215-75

For more samples see The NLM Style Guide for Authors, Editors, and Publishers