BibTeX:
@incollection{Various,
  author = {Various},
  title = {Baha’u’llah visits Mulla Husayn and his companions at Fort Tabarsi},
  booktitle = {Baha'i Stories Blog},
  url = {https://bahaistories.blogspot.com/2017/10/bahaullah-visits-mulla-husayn-and-his.html},
}

APA:
Various. Baha’u’llah visits Mulla Husayn and his companions at Fort Tabarsi. In *Baha'i Stories Blog*.

MLA:
Various. "Baha’u’llah visits Mulla Husayn and his companions at Fort Tabarsi." *Baha'i Stories Blog*, n.d..

Chicago:
Various. "Baha’u’llah visits Mulla Husayn and his companions at Fort Tabarsi." In *Baha'i Stories Blog*, n.d..