The following page and word count for the prose books ought to prove how much work went into each:
Some Things Strange & Sinister   330pp   92,979 words
Some More Things Strange & Sinister  322pp  96,931 words
Pursuing The Strange & Weird       240pp  66, 911 words
The Bizarre Legend & Crimes of Spring Heeled Jack   54pp  19,138 words
Red Paper:Canids   202pp  67,261 words
The Girt Dog of Ennerdale  42pp    13,527 words
Strange & Mysterious Beasts   324 pp  70,539 words
UFO Contacts:Looking At The Evidence 530pp  171,972 words
Unidentified –Identified  220pp  73,671 words
Contact! Encounters with Extra Terrestrial Entities?  370pp  140,865 words
The Hooper Interviews  365pp   78,672 words
Total Word Count: 824,555
Of course that does not include the hundreds of images -some very rare of thought to have been lost 100-120 years ago, illustrations and countless reference and everything is factual -no lies or twisting facts to sell the book like most authors dealing with "World Mysteries"

