GZ Cnc: indeed superoutburst YYYYMMDD(UT) mag observer 20170131.648 <154 (Hiroyuki Maehara) 20170201.574 <139 (Tsuneo Horie) 20170202.530 130 (Rod Stubbings) 20170202.533 125 (Tsuneo Horie) 20170203.558 124 (Tsuneo Horie) 20170203.674 126 (Hiroyuki Maehara) 20170203.994 126 (Eddy Muyllaert)