APA-viite (7. p.)
Kreeft, P. (1990). Everything you wanted to know about heaven... but never dreamed of asking (First complete edition.). Ignatius Press.
Chicago-viite (17. p.)
Kreeft, Peter. Everything You Wanted to Know About Heaven... but Never Dreamed of Asking. First complete edition. San Francisco: Ignatius Press, 1990.
MLA-viite (9. p.)
Kreeft, Peter. Everything You Wanted to Know About Heaven... but Never Dreamed of Asking. First complete edition. Ignatius Press, 1990.
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