"Psychovampires: A Positive Approach to Energy Suckers" was first published as a book in 2009 by Orell Füssli Verlag. The 7th edition was published in 2018 (with a new cover), so that a total of 15,000 paperback copies were published. In German, ten editions have thus been published to date (as of August 2018) with a total of over 20,000 copies.
Foreign-language editions: Albanian, Russian, Lithuanian, Romanian and English, available at amazon.de
In Russian, among others, 20,000 copies have been printed by Alpina Verlag in Moscow: https://alpinabook.ru/catalog/book-psikhovampiry/