Three Comments

Translater's note: This article is the translated version of a proceedings report of a talk given in the workshop ``Nuclear Collective Motion" held May 18-20, 1967 at the Research Institute for Fundamental Physics (now Yukawa Institute for Fundamental Physics), Kyoto University. The proceedings was published in Soryushiron Kenkyu (vol. 35 (1967), page E47-E50), in Japanese. The translation was intended to be as direct as possible. The words in the square brackets in italic (i.e., [italic]) are additions by the translater. Some trivial mistakes have been corrected in the translated version.