types
        
          Course :: name: seq of char
                           credits: ECTSs;
        
          ECTSs = map ACMtopic to nat1;
        
          CourseId = token;
          IdDeg = token;
          StudentId = token;
          ACMtopic  = token;
          Classif  = real;
        
          Univ :: courses: map CourseId to Course
                degrees: map IdDeg to ECTSs
                students: map StudentId to (IdDeg * map CourseId to Classif)
                        topics: map ACMtopic to ACMtopic