BibTeX:
@incollection{Various,
  author = {Various},
  title = {The next morning ‘Abdu’l-Bahá was preparing to leave for Vienna, when},
  booktitle = {bahaistories.com archive},
  url = {https://bahaistories.com/subject/selfless},
}

APA:
Various. The next morning ‘Abdu’l-Bahá was preparing to leave for Vienna, when. In *bahaistories.com archive*.

MLA:
Various. "The next morning ‘Abdu’l-Bahá was preparing to leave for Vienna, when." *bahaistories.com archive*, n.d..

Chicago:
Various. "The next morning ‘Abdu’l-Bahá was preparing to leave for Vienna, when." In *bahaistories.com archive*, n.d..