In 2013, a British website the Kernel published an article accusing Amazon, Kobo, and other e-book retailers of containing books with erotic material such as "rape, incest, and 'forced sex' with young girls." It turned out that these were books written by self-published writers who wrote erotica books. Amazon responded to the Kernel's article by removing books under the categories mentioned in the article, including books depicting rape, incest, and child pornography. In response, some self-published writers engaged in a protest against Amazon's censorship, which had implicated some books that did not include erotic material as offensive as what Amazon should be and was targeting.