Here are some Essential Links to anyone interested.
No.1: The Diving Regulations: ( Translated Into English ) Including Dockside Tests, Trimming and Regulating The Boat, Proper Commands, Etc.
http://www.uboatarchive.net/Diving/D...egulations.htm
in German:
http://www.uboatarchive.net/Diving/D...ionsGerman.htm
No.2: U Bootskunde für U Boote Bauart VII C, Stand vom 15.07.40, M.Dv. 371, 181 ( U-boat Information for U-boat Type VII C, Effective 15.07.40, Navy Off. Inst. 371, 181 ) All Essential Information on the Type VIIC not available in Wikipedia, or many places elsewhere other than U-boat Archive.
http://www.uboatarchive.net/Manual/Manual.htm