In each case you mention, the spelling without the "a" occurs in the printed form of Yogananda's signature (and the memorial plaque). Everywhere else in the book the spelling is with the extra "a". The printed signatures also appear as P. Yogananda, P.Y., Swami Yogananda etc. which is why it appears the writer has taken care to always give the correct spelling as it was written by Yogananda. That is why the spelling with the "a" on page 184 is significant.
