BibTeX:
@incollection{Various,
  author = {Various},
  title = {He added that one should wear black only as a convenience, because it does not…},
  booktitle = {bahaistories.com archive},
  url = {https://bahaistories.com/subject/cleanliness},
}

APA:
Various. He added that one should wear black only as a convenience, because it does not…. In *bahaistories.com archive*.

MLA:
Various. "He added that one should wear black only as a convenience, because it does not…." *bahaistories.com archive*, n.d..

Chicago:
Various. "He added that one should wear black only as a convenience, because it does not…." In *bahaistories.com archive*, n.d..