BibTeX:
@incollection{StaroftheWestEditors,
  author = {Star of the West Editors},
  title = {A Holy Day Kept: How the Friends Honour the Ninth of Riḍván},
  booktitle = {Star of the West},
  publisher = {Bahai News Service},
  url = {https://bahai-library.com/star_of_the_west},
}

APA:
Star of the West Editors. A Holy Day Kept: How the Friends Honour the Ninth of Riḍván. In *Star of the West*. Bahai News Service.

MLA:
Star of the West Editors. "A Holy Day Kept: How the Friends Honour the Ninth of Riḍván." *Star of the West*, Bahai News Service, n.d..

Chicago:
Star of the West Editors. "A Holy Day Kept: How the Friends Honour the Ninth of Riḍván." In *Star of the West*, Bahai News Service, n.d..