1. 1. Mayo Clinic. Menstrual cycle: What's normal, what's not. 2021. Retrieved from: https://www.mayoclinic.org/healthy-lifestyle/womens-health/in-depth/menstrual-cycle/art-20047186.
2. 2. World Health Organization. Menstrual hygiene in schools: Teacher manual. 2017. Retrieved from: https://apps.who.int/iris/bitstream/handle/10665/254169/9789241512169-eng.pdf.
3. 3. UNICEF. Menstrual hygiene: A definition suitable for global monitoring. 2019. Retrieved from: https://www.unicef.org/wash/files/Menstrual_Hygiene_Definitions.pdf.
4. 4. Hoffman M, Bell C, Coll A. Menstrual hygiene management in low-income countries. Washington, DC: Water and Sanitation Program. 2017.
5. 5. Das P, Sarkar M, Mukhopadhyay DK. Menstrual hygiene: How hygienic is the adolescent girl? Indian J Community Med 2018;43(2):74–80. DOI: 10.4103/0970-0218.40872.