Wikimedia
Wikipedia: Klinefelter's Syndrome
Wikipedia entry for Klinefelter's Syndrome in both mammals and adults. Links are also given for additional information on related subjects.
American Academy of Family Physicians
Family doctor.org: Breast Problems in Men
The flowchart on male breast problems in this article allows you to link symptoms with possible diagnosis and treatment. Includes possible symptomns of gynecomastia and male breat cancer.