“…In fact, people have put a great deal of time and effort into the investigations of various ROLs for generalized inverses of matrix products, in particular, researches of (1.9) – (1.12) have already been flourished and diversified in contents since that beginning (cf. [1] , [13] , [14] , [21] , [24] , [30] , [33] , [34] , [44] , [51] , [52] , [73] , [74] , [75] , [113] , [114] , [115] , [121] , [122] ). In spite of much effort devoted to the researches to ROLs problems in the past several decades, most parts of (1.9) – (1.12) remain unresolved.…”