Publications below by Douglas R. White, esp. 1983, explain the method. Exact significance tests are computed for 2 by 2 contingency tables and for 3-way or 2 by 2 by 2 tables (significance test of 3-way interaction):1994 Fisher-B: A Program for an Exact Significance Test for Three-Way Interaction Effects World Cultures 8(2): 40-43.
download fisher-b.exe (c) Douglas
R. White as Shareware, Fortran re-embedded in C+ for Windows by Patrick Gray
download original DOS version as 2or3way.exe
download original DOS version as 2or3way.for
Fisher-b ManualYou can download the fortran version and instructions from here. For the PC open accessories/DOS and navigate in DOS to the directory where you locate the program and type its name. Then follow the instructions