Fulves, Karl: Robert Neale's Trapdoor Card ©1983 Karl Fulves Softcover, saddle-stitched, 5.5x8.5", 12 pages

Image courtesy eBay seller Floshubby

Comments: Illustrated by Joseph K. Schmidt. Denis Behr's Conjuring Archive notes there is an edition with some extra pages (13-17); it's not clear when these pages were added.

Contents (courtesy Evan Shuster, magicbooks.be):

1 Introduction
2 Twist and Link
3 Robert Neale’s Submarine Card
5 Stepping Thru A Playing Card
6 The Trapdoor
9 Streamlined Trapdoor
9 Belt Buckle
10 Double Buckle
11 Flat Klein
11 Slade’s Braid
11 Easy Unlink
12 Topological Untrap

Added to 2nd edition(?)
13 Step by Step Trapdoor
15 Harry Franke's Topological Tricks