The Journal of Preventive Medicine published a special issue on sleep in 2011 that you should not miss if you suffer from sleep disorders.
This special issue on sleep was actually published in July 2011, but its content is very informative and leads to a better understanding of sleep problems and their triggers.
Renowned scientists have done educational work on sleep here.
Among other things, a study on the earthing of beds and a contribution by Prof. Dr. Karl Hecht on the subject of “The geomagnetic field as a biological regulator and its sensitivity to electromagnetic frequencies” will be discussed. Very informative!