It is an open problem whether a function, subharmonic with
respect to the first variable and harmonic with respect to the second,
is subharmonic or not. Based again on our mean value type inequality, we improve our previous subharmonicity results of the above type
functions, thus improving also the previous results of Kołodziej and
Thorbiörnson and Imomkulov. Moreover, we give refinements, with
concise proofs, to the older basic results of Arsove, and of Cegrell and
Sadullaev.
Keywords: Subharmonic, quasinearly subharmonic, separately quasinearly subharmonic, harmonic, net measure, Minkowski content
