Watch the Appendix online guitar lesson by David Hamburger from New School Fingerstyle

The alternating thumb style has been named Travis Picking, for Merle Travis, but it was also the cornerstone of the styles of many of the most influential early bluesmen , including Mississippi John Hurt, Blind Blake, Reverend Gary Davis and Blind Boy Fuller. In fact, guitarists who came of age during the Folk Revival of the late 1950s and early 1960s often refer to alternating-thumb fingerpicking as "John Hurt style." My advice? Check out Hurt for his beautiful relaxation and Blake for his stunning virtuosity.
Reference Source: Blind Blake (http://www.garlic.com/~tgracyk/blake1.htm)