10701
Since a Hausdorff space is the same as a preregular T space , a regular space which is also T must be Hausdorff ( and thus T ) .
 Hausdorff, T, T, Hausdorff
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Hausdorff, T, T, Hausdorff