Thomas Campbell : My Big TOE (english) 
Thomas Campbell is a physicist who used to work for NASA. After his university graduation he did experiments together with Bob Monroe related to consciousness and out-of-body experiences. Thomas taught his own consciousness to "leave his body" and explore non-physical realities. He applied his scientifically trained rational mind as a physicist to his experiences and over the following 30 years developed his "Big TOE" (Theory of Everything) in which he brings together physics and metaphysics into a unity.
In his book Tom describes his experiences of the physical and the non-physical reality as well as his conclusions on how reality seems to be constructed. Don't get scared off by the volume of this book, it is definitely one of the most important theories ever compiled to explain the nature of reality and Tom does a really excellent job at explaining his findings and conclusions.
A highly recommended book, available for free on Google-books : My Big TOE
Alternatively you can buy the book on Amazon.