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Mirrors > Home > MPE Home > Th. List > wss  Structured version Unicode version 
Description: Extend wff notation to include the subclass relation. This is read " is a subclass of " or " includes ." When exists as a set, it is also read " is a subset of ." 
Ref  Expression 

cA  
cB 
Ref  Expression 

wss 
Colors of variables: wff set class 
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