  In this Comment, we show that the paper by Qi Li, D. Belitz and J. Toner,
published in Phys. Rev. B {\bf 79}, 054514 (2009), contains an incomplete
mean-field analysis of a simple model of Ginzburg-Landau type. The latter
contains a stable non-unitary phase, which has not been found in this study and
is missing in the outlined picture of possible stable phases. In this Comment,
the mean field analysis has been corrected, the errors have been explained in
details and relevant topics have been discussed. Shortcomings in the
mean-field-like and renormalization group studies in the mentioned paper have
also been revealed.
