See this order
No.1 docs (great medical content + free leech on many of them)
No.2 bitme (great medical content)
No.3 elbitz (good medical content)
No.4 learnbits (fewer medical content)
No.5 bitspyder (very few medical content)
Till now there is no specialized medical tracker .
Try ebooksshares.org
Its currently open for signups.
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