BibTeX:
@incollection{Various,
  author = {Various},
  title = {The National Association for the Advancement of Coloured People},
  booktitle = {bahaistories.com archive},
  url = {https://bahaistories.com/subject/race-unity},
}

APA:
Various. The National Association for the Advancement of Coloured People. In *bahaistories.com archive*.

MLA:
Various. "The National Association for the Advancement of Coloured People." *bahaistories.com archive*, n.d..

Chicago:
Various. "The National Association for the Advancement of Coloured People." In *bahaistories.com archive*, n.d..