Petty Officer First Class Donald L. Hall, USN (ret.) was a team leader for USGF Team 1 in Vietnam from 1967 to 1971.  In January 1971 he was captured.  In April 1971, he escaped.  He was medically evacuated to the United States.  After his recovery, he went on to earn his Ph.D. D.L. Hall “lives in the mountains of Appalachia with his wife and his three huskies. He is a retired decorated Vietnam Veteran. He has a PhD. in Morphology and Anatomical Structures of prehistoric creatures with the emphasis on fossilized bone matter and DNA/Genetics. Donald L. Hall has published in several scientific journals, including: Studies on extinct anatomical structures of fossilized bone and bone marrow of carnivores in the Cretaceous period; and, Comparative research on extant/extinct bone structure and bone marrow toxicity in Ice Age Mammals.” Petty Officer First Class Donald L. Hall is the author of The Cross-Over Chronicles Book One. 

According to the book description of The Cross-Over Chronicles Book One, “Between 1939 and 1960 three superpowers began a research project unknown to the rest of the world.  Only a chosen few were to take part.  So secretive was this research that the findings of each day, month and year were kept to only the nucleus of the research scientist that were participating.  They were involved with a process unheard of that no one understood:  Genetics, DNA, and Replication.  Failures and success evolved but as time went on the project was stopped.  No one knows the reason why.  Location, books, research papers and formulas disappeared, left to vanish in a location that time would forget.”