Discovering the Mammoth by John J. McKay, a 264-page historical account of the scientific discovery of mammoths, is not freely available in full outside of library or trial services. It covers the transition from myths to science, focusing on the discovery of remains and the ivory trade.
You can borrow the digital version for free from local libraries using InfoSoup or try Everand for a free trial. Discovering the Mammoth free ebook download