Vengeance de l'inconnu

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Overview:

Title: Vengeance de l'inconnu
Author: Patrick Svenn
Year: 1956
Publisher: Fleuve Noir
Price: F225
Pages: 218
Binding: Paperback
Type: Novel
Title Reference: Vengeance de l'inconnu
Notes:
- Probable first printing, as per DL and copyright.
- DL = 2nd trimester 1956; undated AI.
- No art credit, but Michel Gourdon is well known for having illustrated all the covers of the "Angoisse" series, and his signature is clearly visible.
- No ISBN, given date.
- Price is in post-WWII "old francs" (in use until 1959), so no decimals.