Mauser Bolt Rifles by Ludwig Olson is fairly definitive source of information on both military and sporting Mauser rifles and the ammunition used in them. Probably more so than Jon Speeds book which concentrates on just the Oberndorf Mauser Sporters (as I understand it).

Probably the best and most sort after Oberndorf Mauser Sporter was the Type A but it did come in 11 different patterns with these patterns differentiated by double or single triggers, a range of different rear sights, not just the 1 fixed and four folding blade version, octagonal and round barrels. The Type A Pattern #1 as described by Wanabebwana is probably the most recognisable and popular Oberndorf Mauser sporter rifle especially in big game calibres in that it was made specifically for the English African safari market so did not have the Germanic features that the other patterns did.