My first source is one year research on 33 subway stations in New York City by the New York Comptroller Scott Stringer and his team to find out why NYC subway stations are so dirty.

https://www.businessinsider.com/why-the-nyc-subway-is-so-dirty-2015-5

My second source is about a statement the New York Gov. Cuomo made at a Press Conference in Albany. ” New York subway system is disgusting and deteriorating, orders cleaning plan”.

https://www.cnbc.com/2020/04/29/new-york-gov-cuomo-says-nyc-subway-system-is-disgusting-and-deteriorating-orders-cleaning-plan.html

These two sources provide real facts on the conditions of the NYC subway stations which would be very useful for my article.