Michelle Obama is signing copies of her gardening book, "American Grown," at a bookstore in Northwest Washington.
Scores of people, including men and women pushing babies in plastic-covered strollers, lined up in the rain Tuesday outside the Politics and Prose bookstore.
Before she took a seat and started signing books, the first lady told patrons to "buy away" because Mother's Day is Sunday.
She said her book, which tells the story of the White House garden, is a great gift.
"American Grown" was published last spring. It is Michelle Obama's first book.
The publisher says more than 175,000 copies have been printed.
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