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CB and CR filters are "light balancing" and "conversion filters" filters, the ones you use to corect for diferences in colour temperature.
Hasselblad they no longer sell filters, except the types you mentioned first) did use the decamired system to name their filters.
Decamired stands for DEca (i.e. x10) MIcro (i.e. 1/1,000,000th) REciprocal (i.e. 1/x) Degree.
To convert from degrees Kelvin (the "degree" in mired) to decamired directly (skipping the deca and reciprocal bits) you use the formula:
DM = 100,000 / degree Kelvin
To go the other way, just go the other way. ;-)
A CB 12 filter is a blue (B) filter providing a shift in colour temperature of 12 decamired.
It is equivalent to the Kodak Wratten 80B, and is used when daylight (balanced film is used with incandescent light sources producing light of about 3400 Kelvin.
A CR 3 is a red (R) filter shifting colour temperature 3 decamired.
It is a correction filter used to correct for the blue cast you get in shade outdoors, under a blue sky. Its Kodak Wratten equivalent is 81B.
Hasselblad did sell a yellow filter, yes. A yellow filter intended to be used as a contrast filter in B&W photography.
It was called (you'll never guess... ;-)) "Y", for Yellow.
They also sold "R" (red), "YG" (yellow-green), "O" (orange) and "G" (green) filters.
Today, you have to get new B60 filters directly from filter manufacturers like B+W or Heliopan.
Or see what you can find used, or on That Auction Site.