See The Hidden Words of Bahá'u'lláh (Wilmette: Bahá'í Publishing
Trust, 1985). See also Kitáb-i-Íqán (Wilmette: Bahá'í Publishing
Trust, 1989), 68-9, and also Gleanings from the Writings of
Bahá'u'lláh. (Wilmette: Bahá'í Publishing Trust, 1976),
261-4. Trans. Shoghi Effendi.
The Promulgation of Universal Peace: Talks Delivered
by `Abdu'l-Bahá during His Visit to the United States and Canada in 1912
(Wilmette: Bahá'í Publishing Trust, 1982), 52-54.
See,
for example, Gandhi's emphasis on education (even for adults) in his
Constructive Programme: Its Meaning and Place, which may be
found in The Selected Works.