Is there an error, perhaps typographical, in the famous 1939 Oppenheimer-Snyder paper "On Continued Gravitational Contraction" (Phys Rev v56 Sept 1, 1956 pp 455-459)?
Do the units balance in equation 37? The last term inside the last parantheses
##\frac{3r_0^{1/2} \tau}{2R_b^2}##
where...