“…(1.2) and their counterparts on Riemannian manifolds were first studied by Viaclovsky in [63]. Since then, these equations have been addressed by various authors -for a partial list of references, see [1][2][3][8][9][10][11][12]14,[16][17][18][19]24,27,28,[31][32][33]35,[39][40][41]43,44,46,47,53,54,56,64,65] in the positive case and [13,23,25,29,30,42,45,55] in the negative case. When k = 1, these equations reduce to the original Yamabe equation.…”