45951
such as a 1970 report that white-backed swallows in Australia may conserve energy this way , but the first confirmed study that they or any passerine entered torpor was a 1988 study on house martins .
 Australia
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Australia