You can buy previous years editions cheap, and they do not change (much) from year to year as new discoveries in the basic sciences are so rare.

A couple books will cover all your math/physics/chemistry bases, and you can fill in any odds and ends with other material.

Sure beats having to lug around all the materal/heat/ balances/transfer /chem/organic chem/p chem /statics/calculus/diff eq/ physics/electrical eng/statics/etc books around with you. The CRCs have it all, once you know where to look (though you might have a little derrivation work to simplify equations to common applications).

I know I got by with CRCs and my HP-51CX (advanced math pack).

Good Luck!