2 books, "Physiology In Depth" and "Decompression In Depth". Paperbacks, good condition, $5.00 each or $8.00 for both. Each book has light highlights on some pages, not bad. Books published by PADI in 1979 and 1982. Physiology In Depth book is 56 pages and interesting contents include, Physiological Concerns of Women Scuba Divers. The Decompression In Depth book is 86 pages and contents include a very interesting section on Problems of Altitude Diving and Flying After Diving. I'm in Gresham Oregon by Gresham Golf Course. Text or Email ok. Thank you for looking.