Singular values of generalized $\lambda$ functions
  We study special values of a modular function $\Lambda$ which is one of generalized $\lambda$ functions. We show special values of $\Lambda$ at imaginary quadratic points are algebraic integers. Further we prove that $\Lambda$ and the modular invariant function generate the modular function field with respect to the modular subgroup $\Gamma_1(N)$. 
Noburo Ishii
math.NT