Lindemann, W. (1989). Was macht der Frosch im Winter? Kinderbuchverlag.
Citazione stile Chigago Style (17a edizione)Lindemann, Werner. Was Macht Der Frosch Im Winter? Berlin: Kinderbuchverlag, 1989.
Citatione MLA (8a ed.)Lindemann, Werner. Was Macht Der Frosch Im Winter? Kinderbuchverlag, 1989.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.