THIS IS A VERY OLD BOOK (1973) PUBLISHED BY THE EDITORIAL PROGRESS

        IN THE FORMER SOVIET UNION AND WILL ONLY INTEREST YOU IF YOU ARE A 

        LOVER OF THE ISSUE (NOT UNIVERSITY STUDENTS PREPARING EXAMS) ,

        AND THE LANGUAGE IS -------------- FRENCH-------------------------




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        FIVE CHAPTERS:

        1 Préliminaires
    
        2 équations hyperbolyques

        3 équations de Laplanche

        4 Transformations de Laplanche

        5 Méthodes aux différences pour résoudre les éq. aux derivées partielles

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note: the PDF is a good quality one , and although the printing style is that of the 1970s , the book can be read perfectly (personally i think is beautiful , but that´s so because i am a fool).