E. Ślizień Kuczapska, J. . Smyczyńska, and M. Rabijewski, “Selected issues of reproductive health formation disorders in girls. Is it worth to include cycle observation in medical practice? Part I. Natural course of puberty in girls – borders of physiology and pathology”, FeR, vol. 43, no. 3, pp. 285–302, Oct. 2020, doi: 10.34766/fetr.v43i3.319.