The Ultimate Threshold

From Author Wars - https://authorwars.com/publications/the-ultimate-threshold-49028.html

Overview:

Title: The Ultimate Threshold
Author: Mirra Ginsburg
Year: 1970
ISBN-10: 0030818478
Publisher: Holt, Rinehart and Winston
Price: $5.95
Pages: xi+244
Binding: Hardcover
Type: Anthology
Title Reference: The Ultimate Threshold
Notes:
- Stated first edition. (No number line). The WorldCat entry below gives the date as "[1970]", which means they've confirmed it as being published in 1970. However, the LCCN number is "79-...", which implies a publication date of 1979 or 1980, even though the LCCN record below also gives the date as "[1970]". The U.S. Copyright Office, which has all records from 1978 forward available online, does not include a record for this book. Thus while the LCCN number seems to imply a later publication date, the rest of the evidence says that this book was published in 1970, and we list it that way.