5.P Boyle et al. Meta-analysis of clinical trials of permixon in the treatment of symptomatic benign prostatic hyperplasia. Urology 2000 55: 533-539. http://www.ncbi.nlm.nih.gov/pubmed/10736497
6.Wilt TJ, Ishani A, Rutks I, et al. Phytotherapy for benign prostatic hyperplasia. Public Health Nutr. 2000 Dec;3(4A):459-72. http://www.ncbi.nlm.nih.gov/pubmed/11276294
7.Debruyne F, Koch G, Boyle P, et al. Comparison of a phytotherapeutic agent (Permixon) with an alpha-blocker (Tamsulosin) in the treatment of benign prostatic hyperplasia: a 1-year randomized international study. Prog Urol. 2002 June;12(3):384–394. http://www.ncbi.nlm.nih.gov/pubmed/12189744