UPDATE: (CNN) -- The late author/poet Maya Angelou was well-known for her many thought-provoking quotes, but it appears that one that was used for her stamp is not actually hers.
The Washington Post reports that a new United States postage stamp bearing Angelou's likeness features the quote "A bird doesn't sing because it has an answer, it sings because it has a song." Problem is, that's a quote from a book of poems by Joan Walsh Anglund.
"Yes, that's my quote," Anglund told the Post on Monday.
The paper reports that the quote appears in Anglund's 1967 book "A Cup of Sun." The pronouns and punctuation were changed, with "he" in the original verse changed to "it" on the stamp.
A spokesman for the Postal Service defended the use of the quote on the "forever" stamp, saying it had been widely attributed to Angelou.
"The Postal Service used her widely recognized quote to help build an immediate connection between her image and her 1969 nationally recognized autobiography, 'I Know Why the Caged Bird Sings,' " spokesman Mark Saunders said.
The agency hasn't said whether it will reissue the stamp with a different quote.
After the USPS was informed that Anglund had confirmed the quote was hers, the spokesman said in an email to the Post that "Had we known about this issue beforehand, we would have used one of (Angelou's) many other works. ... The sentence held great meaning for her and she is publicly identified with its popularity."
President Obama attributed the quote to Angelou in his remarks at the presentation of the 2013 National Medal of Arts and National Humanities Medal.
"The late, great Maya Angelou once said, 'A bird doesn't sing because it has an answer, it sings because it has a song.' Each of the men and women that we honor today has a song -- literally, in some cases. For others, it's a talent or a drive or a passion that they just had to share with the world."
Anglund appeared to take the mishap in stride, saying, "I think it easily happens sometimes that people hear something, and it's kind of going into your subconscious, and you don't realize it.
"I love her and all she's done, and I also love my own private thinking that also comes to the public because it comes from what I've been thinking and how I've been feeling," she said.
The stamp was to be unveiled Tuesday morning in a ceremony attended by dignitaries including first lady Michelle Obama.
Read more at CNN.
PREVIOUSLY: US Postal Service Honors Maya Angelou With Forever Stamp
(NBC) -- The U.S. Postal Service announced on Monday that Maya Angelou will be honored with a Forever Stamp. Angelou, who passed away in May of 2014, was a beloved poet and novelist who campaigned for human rights.
"Maya Angelou inspired our nation through a life of advocacy and through her many contributions to the written and spoken word," said Postmaster General Megan J. Brennan. "Her wide-ranging achievements as a playwright, poet, memoirist, educator, and advocate for justice and equality enhanced our culture."
In a written statement, the US Postal Service stated that further details regarding the release date will be given out at a later time.
Read more at NBCNews.
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