Research evidence for cranial bone mobility:

http://www.icnr.com/articles/radiographic-evidence-of-cranial-bone-mobility.html

​Research on cranial rhythmic impulse and the Traube-Hering-Mayer oscillation:
http://jaoa.org/article.aspx?articleid=2092406 

Research on measuring intracranial wave form pulsatility:
http://www.ncbi.nlm.nih.gov/pubmed/9779147