Text ( visual ) : unmediated Masers / J. R. Singer. -- New York : Wiley , c1959. -- xi, 147 p. : ill. ; 24 cm. -- Includes bibliography ; Ill. on linig papers. -- (BA10715167) ; https://ci.nii.ac.jp/ncid/BA10715167 Author Heading(s): Singer, Jay R. (Jay Ralph). -- Classification(s): LCC : TK7872.M45 ; DC : 621.38151. -- Subject Heading(s): LCSH : Masers