The Invisible Master

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Overview:

Title: The Invisible Master
Author: Ruger
Year: 1930
Type: Interior Art

Editions/Publications:

Unknown. Scientific Detective Monthly, April 1930 (Unknown, Ruger, Techni-Craft Publishing Corp., $0.25, 100 pages, bedsheet, MAGAZINE)
2024 . The Invisible Master (2024, Ruger, Project Gutenberg, $0.00, ebook, Chapter Book)