An analogue of the Levy-Hincin formula for bi-free infinitely divisible distributions Yinzheng GuHouben HuangJames Mingo Indiana University Mathematics Journal 2016 text pdf 10.1512/iumj.2016.65.5911 10.1512/iumj.2016.65.5911 en Indiana Univ. Math. J. 65 (2016) 1795 - 1831 state-of-the-art mathematics http://iumj.org/access/