BibTeX:
@incollection{BahChronicleseditors,
  author = {Bahá'í Chronicles editors},
  title = {The Nephew Who Was a Letter of the Living},
  booktitle = {Bahá'í Chronicles},
  url = {https://bahaichronicles.org/mirza-muhammad-baqir-bushrui/},
}

APA:
Bahá'í Chronicles editors. The Nephew Who Was a Letter of the Living. In *Bahá'í Chronicles*.

MLA:
Bahá'í Chronicles editors. "The Nephew Who Was a Letter of the Living." *Bahá'í Chronicles*, n.d..

Chicago:
Bahá'í Chronicles editors. "The Nephew Who Was a Letter of the Living." In *Bahá'í Chronicles*, n.d..