We present Floquet calculations of the total rate for multiphoton ionization of atomic hydrogen by a coherent superposition of the second and third harmonics of a Nd:YLF (neodymium-doped yttrium-lithium-fluoride) laser Beld. The total rate depends little on the relative phase of the two 6elds in the range of intensity considered.PACS number(s): 32.80.Rm