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Lyubomir Ivanov (, born 7 October 1952 in Sofia ) is a scientist, non-governmental activist, and Antarctic explorer. He is a graduate of the St. Kliment Ohridski University of Sofia with M.S. degree in Mathematics in 1977, and earned his PhD from Sofia University in 1980 under the direction of Dimiter Skordev, with a dissertation entitled Iterative Operative Spaces.
 place of birth: Lyubomir Ivanov, Sofia
Given a phrase that describes the relationship between two words, extract the words and the lexical relationship between them. The output format should be "relation1: word1, word2; relation2: word3, word4". 
Option: place of death, place of birth, education degree, education institution 
Text: {0} 
Answer:
 place of birth: Lyubomir Ivanov, Sofia