I wonder if we had the same guy, Russian, with his own formalism and his own textbook published online? I remember thinking it may well have had merit but since most of us in there were applying the subject matter in our respective fields which stuck to the traditional formalism. .. it was a challenge.<p>I think it was a special form of multi variable, forget what he called it. Lecture was in mining. Honestly I went to lecture too rarely to give fair judgement