Hagboldt, P., & Morgan, B. Q. (1933). Graded German readers: Books one to five (Books one to five.). Heath.
Citazione stile Chigago Style (17a edizione)Hagboldt, Peter, e Bayard Quincy Morgan. Graded German Readers: Books One to Five. Books one to five. Boston [u.a.]: Heath, 1933.
Citatione MLA (9a ed.)Hagboldt, Peter, e Bayard Quincy Morgan. Graded German Readers: Books One to Five. Books one to five. Heath, 1933.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.