63916
First experiments were held in 1937 on a Heinkel He 111 , piloted by test-pilot Erich Warsitz at Neuhardenberg , a large field about 70 kilometres east of Berlin , listed as a reserve airfield in the event of war .
 Heinkel He 111, Erich Warsitz, Neuhardenberg, Berlin
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 Heinkel He 111, Erich Warsitz, Neuhardenberg, Berlin