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Books available for further study of the biological UFO phenomenon

Quest for the Invisibles by Nik Hayes

Quest for the Invisibles - The debut book by UK based UFO researcher and photographer Nik Hayes, and covering his first five years of work exploring the infrared and ultraviolet parts of the electromagnetic spectrum. Influenced by the earlier work of Trevor James Constable, Hayes set out on his own quest to capture footage of invisible UFOs, experimenting with various attraction, detection and photographic techniques along the way. The book contains dozens of photographs of invisible biological UFOs and other strange objects, captured in the skies above his research area near Oxford, as well as tips and hints explaining how you too could take your own footage of invisible UFOs using readily available photographic equipment. Quest for the Invisibles also references the pioneering work of Trevor James Constable, as well as Luciano Boccone and the Italian UFO research group, the GRCU.

150 pages, US/$14.95 UK/£10.95

The Cosmic Pulse of Life by Trevor James Constable

The Cosmic Pulse of Life - Trevor James Constable's classic book presents evidence that UFOs are mainly invisible and consist of physical craft and living biological creatures. Constable went on to photograph both types of these UFOs using a standard camera loaded with infrared  film, some of which are featured in this updated and expanded edition. Despite his bold leap into the future, the general public and official ufology have a hard time accepting the evidence. In more recent years, teams of engineers in both Italy and Romania, unaware of Constable's earlier discoveries, obtained virtually identical infrared photos, which were published in Italy. In 1996 in what has come to be referred to as the "Tether Incident," NASA managed to record swarms of invisible UFOs that looked remarkably similar to Constable's earlier photographs, using ultraviolet sensitive video tape. Examples of these are given in this book. Also mentioned are some of the other great pioneers of their time who influenced Trevor throughout his life, such as Dr. Wilhelm Reich, Rudolph Steiner, and Dr. Ruth Drown.

354 pages, US/£29.95 UK/£19.95

They Live in The Sky by Trevor James Constable

They Live in the Sky - Trevor James Constable's first full length book reissued, which reveals otherwise hidden creatures and objects traversing our skies that were exposed by his ground breaking infrared techniques. Also covered is a series of telepathic communications the author had with what was claimed to be an extra-terrestrial intelligence. He abandoned this line of research in future work because much of the information received could not be fully verified, and he felt that delving into it more deeply could affect his other work on important scientific levels. Therefore, his work is entirely unique - mapping out a serious scientific pursuit of hidden beings and objects in our atmosphere with the experience of strange, telepathic communications. This book also references the work of the main UFO researchers of the time, including Major Donald Keyhoe, George Adamski, Harold Wilkins and George Van Tassel. Includes 36 original photos by Constable, accompanied by a chapter devoted entirely to their study.

306 pages, US/$24.95 UK/£17.95

All titles published by The Book Tree, San Diego, California, USA.

Available from 


Barnes and 

Can also be ordered from any good bookstore

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