Être et Temps
Heidegger had broken away from the intellectual movement started by Edmund Husserl, whose assistant he had been at University of Freiburg before coming to Marburg. This was a period when Heidegger was preparing his lectures on Kant, which he would develop in the second part of his (Being and Time) in 1927 and (1929). Although Heidegger had dedicated the first edition of "Being and Time" to Edmund Husserl, Husserl gave the book a poor review, and in the second edition Heidegger removed that dedication.