BibTeX:
@incollection{Various,
  author = {Various},
  title = {Elizabeth and the Rope Swing},
  booktitle = {Baha'i Stories for Children},
  url = {https://bahaistoriesforchildren.blogspot.com/2018/05/being-good-and.html},
}

APA:
Various. Elizabeth and the Rope Swing. In *Baha'i Stories for Children*.

MLA:
Various. "Elizabeth and the Rope Swing." *Baha'i Stories for Children*, n.d..

Chicago:
Various. "Elizabeth and the Rope Swing." In *Baha'i Stories for Children*, n.d..