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Questions relating to designing PCBs
By lyndon
Those specific drawings originate from the National Semiconductor Linear Applications Handbook, but many the circuits themselves may have been published earlier in Walter Jung's IC Op-Amp Cookbook. National Semiconductor is now owned by Texas Instruments.

I'm a pretty good mood today :-) If you provide me with an address in the US, I'll send you my old, dog-eared copy of the National Apps book (it was already well-thumbed by the time I got it). Weighs about 5 pounds and I haven't cracked it open in years. Guarantee you'll learn a ton from it if you're interested in linear circuits.