I think this issue has been grappled with in the past but I would still suggest the following:
Surgery
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1. Essentials of General Surgery by Lawrence
2. High-Yield by Nirula
Medicine
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1. Cecil Essentials of Medicine by Andreoli
2. Blueprints in Medicine
Pediatrics
============
?
OB
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1. High-Yield OB
Psychiatry
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1. Blueprints in Psychiatry