Takacs, Lajos, On the Distribution of the Integral of the Absolute Value of the Brownian Motion, Annals of applied probability , 3(1), 1993, pp. 186-197
Kac has considered the integral of the absolute value of a Brownian motion process and determined the Laplace-Stieltjes transform of the distribution function of this integral. In this paper explicit expressions are given for the distribution and the moments of this integral.