Furi-Martelli-Vignoli spectrum and Feng spectrum of nonlinear block operator matrices
Xiao-Mei Dong(董小梅), De-Yu Wu(吴德玉), and Alatancang Chen(陈阿拉坦仓)
中国物理B . 2021, (4): 40201 .  DOI: 10.1088/1674-1056/abd7df