Just started the book 'Alien World" is a book edited by ufologist Peter Brookesmith, with several contributions by Hilary Evans from 1992, the following information below is courtesy of a review from a chap called Ashtar Command for Amazon.
The book looks like a collection of magazine articles. Indeed, the material was originally published in the British partwork magazine "The Unexplained". It's also part of a series of books called "Mysteries of Mind, Space and Time". At least in Sweden, "Alien World" was the first volume of this series, but I'm not sure in what order they were published in Britain or the United States. Today, "Mysteries of Mind, Space and Time" has been quietly forgotten, but both the books and the original magazine were very popular during the 1980's.