BibTeX:
@incollection{Various,
  author = {Various},
  title = {The Báb Mourns the Heroes of Ṭabarsí},
  booktitle = {Baha'i Stories Blog},
  url = {https://bahaistories.blogspot.com/2018/04/june-july-1849-babs-immeasurable-sorrow.html},
}

APA:
Various. The Báb Mourns the Heroes of Ṭabarsí. In *Baha'i Stories Blog*.

MLA:
Various. "The Báb Mourns the Heroes of Ṭabarsí." *Baha'i Stories Blog*, n.d..

Chicago:
Various. "The Báb Mourns the Heroes of Ṭabarsí." In *Baha'i Stories Blog*, n.d..