After completing his initial university studies he worked as a teacher of German and geography. He earned a doctorate from Humboldt University of Berlin in 1976 with his dissertation on comparative word construction of Esperanto and German. In 1985 he earned a second doctorate from Humboldt on constructed languages. (In the former East Germany such a second degree was known as "dissertation B", corresponding to the highest academic qualification of "habilitation" awarded to full professors in many European countries.) In 1988 the university appointed him "Honorary Lecturer of Interlinguistics."
Having first taught himself Esperanto in 1957, he later became secretary (1968 through 1990) of the Centra Laborrondo de Esperanto-Amikoj ("Central Working Circle of Friends of Esperanto"), a government-sanctioned affiliate of East Germany's Cultural Association (Deutsche Kulturbund). After 1981 the group became a part of the newly founded German Democratic Republic Esperanto Association (Esperanto-Asocio de GDR, GDREA). From 1970 to 1990 Prof. Blanke was also editor of the newsletter of those organizations, Der Esperantist. In 1991 the Esperantists of the former East Germany formally affiliated with the German Esperanto Association (Germana Esperanto-Asocio) which had previously operated only in West Germany.
"Forpasis Detlev Blanke". Libera Folio. Retrieved 11 September 2017. http://www.liberafolio.org/arkivo/www.liberafolio.org/2016/forpasis-detlev-blanke.html ↩