From the book: "Bother!' said Rabbit, "He's gone out." He went back to the green front door, just to make sure, and he was turning away, feeling that his morning had got all spoilt, when he saw a piece of paper on the ground. And there was a pin in it as if it had fallen off the door. "Ha!" said Rabbit, feeling quite happy again. "Another notice!". This is what it said: GON OUT BACKSON BISY BACKSON C.R. "Ha!" said Rabbit again, "I must tell the others". And he hurried off importantly. The nearest house was Owl's, and to Owl's House in the Hundred Acre Wood he made his way.*
From the book.