Brou\'e's abelian defect group conjecture for the sporadic simple Janko   group J_4 revisited
  We show that the 3-block of the sporadic simple Janko group J_4 with defect group C_3 x C_3, and the principal 3-block of the alternating group A_8 are Puig equivalent, answering a question posed in earlier work of Koshitani-Kunugi-Waki. To accomplish this, we apply computational techniques, in particular an explicit version of the Brauer construction. 
Shigeo Koshitani, J\"urgen M\"uller, Felix Noeske
math.RT