the addition of salts [1–6] or in mixed surfactant systems [7–9]. It was also found that several hydrophilic anionic, cationic and nonionic surfactants could form wor
the addition of salts [1–6] or in mixed surfactant systems [7–9]. Itwas also found that several hydrophilic anionic, cationic and nonionicsurfactants could form wor