T. Hasebe, N. Sakuma and S. Thorbjornsen.
The normal distribution is freely selfdecomposable.
Int. Math. Res. Not. IMRN., 2019, no. 6, 1758–1787.

B. Collins, T. Hasebe and N. Sakuma.
Free probability for purely discrete eigenvalues of random matrices.
J. Math. Soc. Japan, 70, (2018), no. 3, 1111–1150.

O. Arizmendi, T. Hasebe and N. Sakuma.
On the law of free subordinators.
ALEA Lat. Am. J. Probab. Math. Stat., 10, (2013), no. 1, 271-291.

N. Sakuma and H. Yoshida.
New limit theorems related to free multiplicative convolution.
Studia Math., 214, (2013), no. 3, 251-264.

V. Perez-Abreu and N. Sakuma.
Free infinite divisibility of free multiplicative mixtures of the Wigner distribution.
J. Theoret. Probab., 25, (2012), no. 1, 100-121.