B&W printing has blueish/greenish cast

[silvershoot]

I ordered and received very quickly 2 copies of a 9 page pocket book. All the original photos are black and white but the reproductions have a decidedly blueish/green cast. Otherwise, the book turned out as I designed it, the contrast and density and resolution are excellent. They very closely match the originals except for the color cast. Any explanations for this? Should I send back for re-prints? Anyone else have this problem with their B&W books?
Thanks