Whitaker's Almanack
Whitaker's Almanack was a reference book published in the United Kingdom on Earth. 

Sherlock Holmes owned an early edition of the book and it provided him the key to the secret code in The Valley of Fear. The holoprogram based on Sherlock Holmes' adventures included a copy of the book. In 2365, Data showed Geordi La Forge the book as one example of the items Holmes collected and explained its significance to the detective. ()

External link
 

de:Whitakers Almanack
fr:Whitaker's Almanack
Earth literature