BibTeX:
@incollection{Various,
  author = {Various},
  title = {The Old Woman with a Stone},
  booktitle = {bahaistories.com archive},
  url = {https://bahaistories.com/subject/sincerity},
}

APA:
Various. The Old Woman with a Stone. In *bahaistories.com archive*.

MLA:
Various. "The Old Woman with a Stone." *bahaistories.com archive*, n.d..

Chicago:
Various. "The Old Woman with a Stone." In *bahaistories.com archive*, n.d..