BibTeX:
@incollection{BahChronicleseditors,
  author = {Bahá'í Chronicles editors},
  title = {The Banner-Bearer Before a King: Lua Getsinger and the Sháh},
  booktitle = {Bahá'í Chronicles},
  url = {https://bahaichronicles.org/lua-getsinger/},
}

APA:
Bahá'í Chronicles editors. The Banner-Bearer Before a King: Lua Getsinger and the Sháh. In *Bahá'í Chronicles*.

MLA:
Bahá'í Chronicles editors. "The Banner-Bearer Before a King: Lua Getsinger and the Sháh." *Bahá'í Chronicles*, n.d..

Chicago:
Bahá'í Chronicles editors. "The Banner-Bearer Before a King: Lua Getsinger and the Sháh." In *Bahá'í Chronicles*, n.d..