Empirical Studies
Secure Phylogenetic Attachment, Dyadic Trauma, and Completion Across the Life Cycle
Joseph P. Riordan, Abi Blakeslee, and Peter A. Levine

Research
The Somatic Experiencing Trauma Institute has published some interesting research related to Somatic Experiencing.

Therapy may be most effective if it facilitates self-awareness and self-regulation.
Bessel van der Kolk