Programmed-Aging.org – Site containing extensive information about aging theories, especially programmed aging theories.
www.azinet.com/aging/ – Books, ebooks, and journal articles on aging theories by Theodore Goldsmith
Introduction to Biological Aging Theory 2nd Ed – ISBN-13 978-0-9788709-1-1 (2014) 44pp. Free PDF format e-book. Also available in various formats from Amazon, Barnes and Noble, etc.