What is a "classic six"? See TEN beautiful examples on the market

Featuring Janet Wang, Bryden McGhee, and Carrie Chiang's listing at 785 Fifth Avenue, Upper East Side, Jessica Buchman and Kristin Miller's listing at 9 Prospect Park West, Park Slope, and Cathy Franklin, Alexis Bodenheimer, and Marion Smith's listing at 930 Fifth Avenue, Upper East Side: https://www.cityrealty.com/nyc/market-insight/features/great-listings/what-quotclassic-sixquot-see-ten-beautiful-examples-market/20582