Stone
From Jenny Everywhere Wiki
Stone published one universe's Jenny's music reviews. They employed Haroun the Thrice Cursed as a review editor. (PROSE: Morning After) Jenny described it as a “major magazine” to Jennifer Dao Chu, noting that her job there got her “into a lot of interesting capers, some of them intentional”. (PROSE: So You're Jenny Everywhere)
Behind the scenes
Scott Sanford wrote in his author's comments that he intended for the Stone to be a reference to the American magazine Rolling Stone, but liked the ambiguity when he realised it could also be interpreted as an analogue of another real-world magazine, Slate.