In a series of recent papers, G. Shimura obtained an exact formula for the mass of a maximal lattice in a quadratic or hermitian space over a totally real number field. Using Bruhat-Tits theory, we obtain a quick and more conceptual proof of his formula when the form is totally definite.
"On an exact mass formula of Shimura." Duke Math. J. 107 (1) 103 - 133, 1 March 2001. https://doi.org/10.1215/S0012-7094-01-10716-3