BibTeX:
@incollection{Various,
  author = {Various},
  title = {Searching for Bahá'u'lláh in the Mountains},
  booktitle = {bahaistories.com archive},
  url = {https://bahaistories.com/subject/bahaullah-sulaymaniyyih},
}

APA:
Various. Searching for Bahá'u'lláh in the Mountains. In *bahaistories.com archive*.

MLA:
Various. "Searching for Bahá'u'lláh in the Mountains." *bahaistories.com archive*, n.d..

Chicago:
Various. "Searching for Bahá'u'lláh in the Mountains." In *bahaistories.com archive*, n.d..