BibTeX:
@incollection{Various,
  author = {Various},
  title = {The Marriage of Louis and Louisa Gregory},
  booktitle = {bahaistories.com archive},
  url = {https://bahaistories.com/subject/race-unity},
}

APA:
Various. The Marriage of Louis and Louisa Gregory. In *bahaistories.com archive*.

MLA:
Various. "The Marriage of Louis and Louisa Gregory." *bahaistories.com archive*, n.d..

Chicago:
Various. "The Marriage of Louis and Louisa Gregory." In *bahaistories.com archive*, n.d..