"Tourism." . . "Toeristenindustrie." . . "Turisme." . . "turisme." . "USA." . . "Planificació turística." . . "Tourisme Problèmes et exercices." . . "Turismo Studi." . . "Tourisme." . . "Turismo." . . . . "Voyages." . . "Tourist trade." . . "Tourismus." . . . . . "The Tourism system : an introductory text" . . . . . . . "The tourism system" . "The tourism system"@en . . "The tourism system : an introductory text"@en . "The tourism system : an introductory text" . . . . . . . . "Problems, exercises, etc" . . "The Tourism system" . . . "Textbooks" . "Textbooks"@en . . . . . . "Tourism system : An introductory text" . . . . . . . "The tourism system : an introd. text" . . . . "Tourism System" . . . . . . . . . . . "The Tourism System" . . . . . . . "The tourism system. An introductory text"@en . . . . . . . "The Tourism System : An Introd. Text" . . . "Lehrbuch" . "Tourism system : an introductory text" . . . . . . . . . . . . . . . . . . . . . "Toerisme." . . "Turism." . .