Magazine  (Nov 1921)  Page(s) 159.  
 
"Mrs. Pleas on Raising Seedling Peonies"
...Kelway's single white, The Queen, was our only plant bearing seeds, blooming before any other kind was open; it was not hybridized, yet from this one planting I have every color and shade from White Swan to Black Beauty. [...]
From this one planting of single white seeds came Elwood Pleas, Midsummer Night's Dream, Gem, Mary, Quaker Lady, Shabona, Mad. Pleas, Walter Morgan, Golden Wedding, Nellie Pleas, Gypsy Queen, Laura E. Pleas, and Rosy Dawn in doubles; and in singles, White Swan, Wild Rose, Golden Cushion, Pocahantas; among the Japanese, Dr. Edgar Pleas, Novelty, Altar Candles, and Golden Nugget represent the best. [...]
—Sarah A. Pleas, Whittier, California

Magazine  (Jul 1921)  Page(s) 129.  
 
Mrs. Pleas' Estimate of Her Own Peonies
Japanese Varieties
Walter Morgan — White, with best yellow center of any at that time; this, too, greatly prized by Mr. Harrison.

Book  (1907)  Page(s) 40.  
 
Walter Morgan, by the same propagator [Pleas], comes next. It is very nearly pure yellow. These, perhaps, have not so much merit in themselves, though they are fine flowers; but we have great hopes of their progeny. We have raised quite a number of seedlings from them, and hope for the best of results, as all wish to see a grand, full double, yellow peony These are rare and high, probably not over fifty in existence.