<prompt> Translate the following text to EnglishKarenga, mwanzilishi wa Kwanzaa, pia ameandika vitabu viwili juu ya sherehe hiyo, Asili, Dhana, Mazoezi na Sherehe ya Familia, Jumuiya na Utamaduni ya Waafrika na Wamarekani.  <response>: Karenga, Kwanzaas creator, has also written two books on the celebration, Origin, Concepts, Practice and The African American Celebration of A Celebration of Family, Community and Culture . And Anna Day Wilde describes how the holiday gained popularity in Mainstreaming Kwanzaa, in Public Interest , No. 