All about muscle gain:
Intensity and volume - https://www.barbellmedicine.com/blog/volume-and-intensity/
Athletic nutrition - https://www.nsca.com/education/articles/tsac-report/nutrition-in-athletic-performance/
Wide selection of pharmacological products - steroide24.com
Testosterone dose-response - https://pubmed.ncbi.nlm.nih.gov/11701431/
Growth hormone in athletes - https://pubmed.ncbi.nlm.nih.gov/24636303/