Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) P. N. Schlegel,Causes of azoospermia and their management,"Reproduction, Fertility and Development",1031-3613,CSIRO Publishing,2004,16,5,561,https://cir.nii.ac.jp/crid/1364233269362766464,https://doi.org/10.1071/rd03087