Hello,
Microsoft published Hyper-V PDF Bibles, all in one location :
Hyper-V PDF Bible Download
https://msdn.microsoft.com/en-us/virtualization/hyperv_on_windows/develop/tlfs
This page contains link for the Hypervisor Top-Level Functional Specification hosted on GitHub. You will be able to down the pdf for 2008 R2, 2012, 2012 R2 and 2012 R2 Revision B.