Yes there is a considerable body of evidence to link Transversus abdominis with pelvic floor function. this link is a useful start.
SAPSFORD, R.R., HODGES, P.W., RICHARDSON, C.A., COOPER, D.H., MARKWELL S.J., JULL G.A.(2001) Co-activation of the abdominal and pelvic floor muscles during voluntary exercises. Neurourology & Urodynamics, 20:31-42.
Clinically you can teach people to"find" their pelvic floor muscles by activating transvers abdominis and vice versa. And optimal pelvic floor function will never be achieved without good TA strength