Another was "Pondoro" Taylor. Bell, Selous, Sutherland and Taylor all led interesting lives, and books by or about them are unfailingly interesting.
Though I suppose it makes many on here cringe, my all time favorite standard for rifle accuracy in the field was Bell's: 4" at one hundred yards - oh, and that was offhand with iron sights. I have any number of rifles that will shoot around or under 1/2" at 100 yards off a bench or bipod, I have seldom been able to meet Bell's standard off hand with iron sights with much consistancy. :
I second Nodak7mm's recommendation to google Safari Press; most of my books on African hunting and hunters have come from them.