The self-published picture book The Rabbit Who Wants to Fall Asleep, which shot to the top of Amazon's U.K. print list a few weeks ago, has officially been acquired by Penguin Random House. PW reported the acquisition last week, but the house did not confirm the news until today. Now the publisher has announced that, in a joint deal between Random House U.S. and Penguin Random House U.K., it has taken world English rights to the book, and two forthcoming titles, from Salomonsson agent Julia Angelin.

While PW has heard that author Carl-Johan Forssén Ehrlin fetched a seven-figure advance, the publisher declined—as is its policy—to comment on this.

Details about the two other stand-alone titles included in the deal will, RH said, "be presented at a later date."

RH's new print edition of Rabbit will be released on October 2—it will be strikingly similar to Ehrlin's current self-published one (which he released through Amazon's CreateSpace unit), featuring a slightly updated cover—in all of the publisher's English-language markets: the U.S., U.K., Canada, Australia, New Zealand, India and South Africa. The e-book edition from RH will be released even sooner, on September 8. Two downloadable audio editions of the book will also be released in the U.S. and U.K. on October 2; one will feature a female narrator, and the other a male narrator. The CD editions of the title, featuring both narrations, will be released on November 3.

In the U.S., Barbara Marcus, president and publisher of Random House Children's Books, brokered the deal, while Francesca Dow, managing director of Penguin Random House Children’s U.K., handled the purchase in the U.K.

The book has ridden a wave of press attention, in part fueled by the author's claim that reading the title to children will lull them to sleep. After Ehrlin, a Swedish behavioral scientist and life coach, released an English-language edition of the book in April 2014, it drew little to no attention. An August 14 article in the U.K.'s The Daily Mail, which seized on the fact that the book was the first self-published title to hit #1 on Amazon U.K.'s print bestseller list, touted Rabbit as the "surprise bestseller" that "made children tired." After the Daily Mail article, stories on the book followed in numerous outlets, including the Guardian, NPR and CBS News. Then the book caught fire, climbing the charts in the U.S. in a heretofore unseen manner. According to BookScan, which tracks an estimated 80% of print sales, Rabbit sold 24 copies for the week ending August 16. The following week, ending August 23, it sold just over 29,000 copies.

Ehrlin released the title in multiple editions—he translated Rabbit into seven languages—after initially publishing it in Sweden in 2011. PRH has also acquired Spanish language rights to the book, with Penguin Random House Grupo Editorial set to release its own edition. (Verlagsgruppe Random House, a German sister company to Penguin Random House, will be releasing a German edition of the book.)

Speaking about the acquisition, Dow called the book "a phenomenon that’s grabbing people’s attention all around the world." Marcus added that she believes PRH will be able to "expand the availability and potential readership" of the book. She said the publisher is confident that "there is a vast audience of eager parents that will both respond to and benefit from The Rabbit Who Wants to Fall Asleep.”

Correction: An earlier version of this article referred to Verlagsgruppe Random House as a division of Penguin Random House. It is not; it is a sister company to PRH.