SINGH, V.; TAMAR, N.; LONE, Z.; DAS, E.; SAHU, R.; MAJUMDAR, S. Association between serum 25-hydroxy vitamin D level and menstrual cycle length and regularity: A cross-sectional observational study. International Journal of Reproductive BioMedicine (IJRM), v. 19, n. 11, p. 979–986, 13 Dec. 2021.