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In 1922 Heitler began his study of physics at the Karlsruhe Technische Hochschule in 1923 at the Humboldt University of Berlin and in 1924 at the Ludwig Maximilians  University of Munich  ( LMU ) where he studied under both  Arnold Sommerfeld  and Karl Herzfeld .
 employee of: University of Munich, Arnold Sommerfeld
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: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
Answer:
 employee of: University of Munich, Arnold Sommerfeld