No TPTP formula. May not be expressible in strict first order.	Government.kif 3055-3055	The day 15 is a date established of world customs organization
No TPTP formula. May not be expressible in strict first order.	Geography.kif 1667-1667	Winter season is equal to the recurring period from December to February
No TPTP formula. May not be expressible in strict first order.	Media.kif 337-337	Christmas day is a subclass of the day 25

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