NEW YORK – It was an unlikely — and coveted — find: a thick United States government file discovered on the back seat of a New York City taxi, its pages containing mug shots, criminal associates and favorite hangouts of over 800 Mafia members during the 1950s and early 1960s. Such notorious figures as Carlo “Don Carlo” Gambino, Meyer Lansky and Salvatore “Lucky Luciano” Lucania each had their own entries.

Nearly 20 years after it was found inside the yellow cab by a passenger, the 3-inch thick, three-ring binder stamped “Mafia” and “United States Treasury Department Bureau of Narcotics” is being offered for sale at Bonhams New York on Wednesday.

Its pre-sale estimate is $10,000 to $15,000.

The file was compiled sometime between 1957 and 1962 by the Bureau of Narcotics, an early iteration of the Drug Enforcement Administration.

Robert F. Kennedy is believed to have used a copy of the file while he was U.S. Attorney General in 1963 during the televised McClellan Hearings into organized crime.

Only 50 copies of the file were believed to have been printed. The one for sale at Bonhams is No. 31.

Geiger said the passenger found the binder inside a black bag on the seat of the cab on a snowy night in the early 1990s after leaving Radio City Music Hall.

“He basically just kept it to himself until contacting HarperCollins in 2006,” said Geiger. The owner, who is connected with the film and music industry in Hollywood, did not wish to be identified by name.

HarperCollins published a facsimile of the book a year later, with some sections redacted. “Wiseguy” author Nicholas Pileggi called the publication “a treasure trove for true-crime buffs and mob aficionados.”

The book is arranged regionally by state and country (Canada, Italy and Mexico). One page is dedicated to each hoodlum and a quick glance identifies New York as the capital of the underworld in the U.S., with 350 criminals listed, followed by California with 58 and Illinois with 45.

On the bottom of each entry are the words: “Property of U.S. Govt — for official use only. Not to be disseminated or contents disclosed without permission of Commissioner of Narcotics.”

Geiger said the cloth cover binder is not dated, except for two pages. One is from 1959, the other from 1962, indicating the files were most likely compiled before the McClellan hearings