Arthur Henry Bullen, Dictionary of National Biography… (1890)
“ Sero sed serio’ (1592?) , 4to (Brit. Mus.) The publisher, Thomas Newman, in the dedicatory epistle to Nicholas Sanders, declares that every word of this tract is Greene's own. We have Chettle's authority for the fact that Greene left at his death many papers, which, fell into the hands of booksellers. The ‘Vision’ may have been put together from some of these papers; but it certainly was not written in his last illness. It begins by declaring that ‘The Cobler of Canterbury’ (an anonymous tract published in 1590) had been wrongly attributed to Greene, much to his annoyance ”
