Recently Discovered Anthology/Collection
The Wolfe Pack: Eight Great Mysteries by Rex Stout

Brought to our attention in 2016 by Philip J. Frye, this 1971 Bantam boxed set in a slip case contains 8 mass market paperbacks:
In the Best Families, And Be a Villain, Plot It Yourself, The Silent Speaker, Death of a Doxy, Too Many Women, Gambit, & If Death Ever Slept

Mr. Frye has also provided the images below of this rare collection. Click on a thumbnail image to view the larger image of it.
[The title of this boxed set pre-dates the founding of our organization, The Wolfe Pack.]