BibTeX:
@incollection{AbdulBah1912,
  author = {'Abdu'l-Bahá},
  title = {The Eleven Principles out of the Teaching of Bahá’u’lláh, Explained by ‘Abdu’l-Bahá in…},
  booktitle = {Paris Talks},
  year = {1912},
  publisher = {Bahá'í Publishing Trust},
  url = {https://www.gutenberg.org/cache/epub/19284/pg19284-images.html},
}

APA:
'Abdu'l-Bahá. (1912). The Eleven Principles out of the Teaching of Bahá’u’lláh, Explained by ‘Abdu’l-Bahá in…. In *Paris Talks*. Bahá'í Publishing Trust.

MLA:
'Abdu'l-Bahá. "The Eleven Principles out of the Teaching of Bahá’u’lláh, Explained by ‘Abdu’l-Bahá in…." *Paris Talks*, Bahá'í Publishing Trust, 1912.

Chicago:
'Abdu'l-Bahá. "The Eleven Principles out of the Teaching of Bahá’u’lláh, Explained by ‘Abdu’l-Bahá in…." In *Paris Talks*, Bahá'í Publishing Trust, 1912.