BibTeX:
@incollection{Various,
  author = {Various},
  title = {Before He left London in 1913 at the close of His second visit, He gave a talk},
  booktitle = {bahaistories.com archive},
  url = {https://bahaistories.com/subject/teaching},
}

APA:
Various. Before He left London in 1913 at the close of His second visit, He gave a talk. In *bahaistories.com archive*.

MLA:
Various. "Before He left London in 1913 at the close of His second visit, He gave a talk." *bahaistories.com archive*, n.d..

Chicago:
Various. "Before He left London in 1913 at the close of His second visit, He gave a talk." In *bahaistories.com archive*, n.d..