AMA Style uses a superscript-style of citation. References are listed at the end of the paper in numerical order. Each source has its own superscript number.
REFERENCES
1. Tremblay MS, Chaput J, Adamo KB, et al. Canadian 24-hour movement guidelines for the early years (0–4 years): an integration of physical activity, sedentary behaviour, and sleep. BMC Public Health. 2017;17:1-32. doi: 10.1186/s12889-017-4859-6
2. Rachman S. Anxiety. 3rd ed. Psychology Press; 2013.
3. Advil Nighttime. Package insert. Pfizer Consumer Healthcare; 2011.