Li. Voronchikhina et Ya. Ryzhkov, SYNTHESIS AND SURFACE-ACTIVITY ON BOUNDAR Y OF AQUEOUS SOLUTION-GAS OF AMMONIUM QUATERNARY-SALTS, CONTAINING 2 LONG-CHAIN RADICALS, Izvestia vyssih ucebnyh zavedenij. Himia i himiceskaa tehnologia, 37(3), 1994, pp. 60-64