--- Pupil's edition.
Horton, John.
Teacher's edition ... Book 3. [1969.] ; Pupil's edition ... Book 3. [1969.] ; Teacher's edition ... Book 4. [1972.] ;  Pupil's edition  ...Book 4. [1972.] ; Teacher's edition ... Book 5. [1972.] ; Pupil's edition ... Book 5. [1972.] ; Teacher's edition ... Book 6. [1972.]  ; Pupil's edition ... Book 6. [1972.]