After Carl Menger, the Austrian school broke into two lines. The main line followed his causal-realist approach of Menger in the work of Boehm-Bawerk, Mises, and Rothbard. The branch line was inspired by Wieser and continued by Hayek.
Joe Salerno has a seminal article on the difference between the two branches as illustrated by the relationship between Mises and Hayek on the issue of economic calculation in a system of central planning.
http://mises.org/journals/rae/pdf/rae6_2_5.pdf
