DIRECTORY kummer.

Contains the files:

biquadratic.forms    
Gives the 4 x 4 array BBB of quadratic forms on the kummer surface
such that, projectively:
( BBB[i,j] ) = ( k_i(A+B) k_j(A-b) + k_i(A-B) k_j(A+B) )

defining.equations   
Gives the defining equation for the kummer surface, and
a formula for addition by a point of order 2.

duplication
Gives the formula for the duplication law on the kummer surface.