“…It is interesting that the instanton contributions to prepotential 17 can be obtained from the evaluation of periods and the prepotentials obtained in this way 18,19,20,21,22,23,24,25,26 are known to be consistent to the instanton calculus. 26,27,28,29,30,31,32,33 In these studies, the method based on Picard-Fuchs equations 18,19,20,21,22,23,24,25,34,35,36,37,38 played a crucial role.…”