The associations between serum sex hormones, erectile function, and sex drive: the Olmsted County Study of Urinary Symptoms and Health Status among Men.
Gades NM, Jacobson DJ, McGree ME, St Sauver JL, Lieber MM, Nehra A, Girman CJ, Klee GG, Jacobsen SJ. J Sex Med. 2008 Sep; 5(9):2209-20. Epub 2008 Jul 4.