Knuth is famous for focusing on writing his books.  He even stopped using email because it was too distracting.  I doubt he has the time (or interest) to export all his writing to modern indexable formats on a site he maintains (Prof. Knuth feel free to yell at me about this assumption).  He is clearly credited.  Just getting the knowledge out there is good.<p>What I find truly astonishing is that this <i>1974</i> paper is so relavent today.