Tim is correct. Unlike a number of manufacturers who, for one reason or another, give colour callouts in terms of brands like Humbrol, Gunze and Tamiya, Mark I have just gone with the generic naming. Sometimes this aids in finding the right paints (e.g. RLM codes are a godsend for Luftwaffe modellers), other times they go with something far more ambiguous like "green". In the end, you will be indebted to do a little research here and there. Fortunately, this is where the Internet does shine. And remember that forums like ours, Britmodeller, Fine Scale Modeler, etc. can steer you in the right direction.
Or confuse the proverbials out of you!

OTB ...
GB20 - AW.650-222 Argosy (MikroMir); GB22 - B-25J Mitchell (Academy-Minicraft); Non-GB - Pe-2 (Decapod 3D)