That article refers to an Oxford `Einstein blackboard'; this University too has an Einstein blackboard, kept by the School of Physics and Astronomy [and last seen in C13]. Scurrilous rumour hath it that the board was once cleaned, and the current writing inscribed by some professor; I expect all EBs have similar rumours!
For the use of mathematics in attribution, see the work of Fiona Tweedie, also this conference, with further references in both cases.
For more general comments on mathematics and literature, see first the general course texts, Kline and Hollingdale. I found Barbara Parkin's home page interesting; she is an educator trying to integrate mathematics into literature. You may also find useful a collection of references made by JoAnne Growney, a poet who incorporates mathematics into her work. Her home page includes references to her own work. Not exactly literature, but Tom Lehrer is a mathematician/satirist who occasionally allowed maths to intrude into his songs, including Lobachevsky, NewMath, There's a delta for every epsilon and others.