This paper is divided into four sections. The first, by Timofeev-Ressovskij, describes the mutagenic effects of x-rays and gamma rays on Drosophila melanogaster; the second part, by Zimmer, analyzes Timofeev-Ressovskij's results theoretically. The third and most remarkable section, by Delbrück, puts forth a model of genetic mutation based on atomic physics. It represents Delbrück's debut in biology. This has been called the “green paper”, referring to the color of the paper cover of the Nachrichten, and also the Dreimännerarbeit of genetics, for the three authors involved. This paper provided much of the material for Erwin Schrodinger's What is life? (1944), a work that takes a "naive physicist's" approach to the problems of heredity and variation; Shrodinger's book is often cited as having inspired Watson, Crick, Wilkins and others to focus their careers on the problems of molecular biology.

Digital facsimile of the 1935 paper from Universität Zurich at this link. English translation of the complete paper with commentary and six essays in Creating a Physical Biology.  The Three-Man Paper and Early Molecular Biology, edited by Phillip R. Sloan and Brandon Fogel (Chicago: University of Chicago Press, 2011).

This work demonstrated the absorption of the phages on the host cell, and the lysis of the host cell and the liberation of a hundred or so daughter paritcles from each cell. It also showed that the particles multiply inside the cells rather than at their surfaces, since unti lysis occurs the number of particles visible at the surface remains constant. 
Digital facsimile from PubMedCentral at this link. For an extensive commentary on this paper, including correspondence between Anderson and Delbruck before and after publication see T. F. Anderson, "Electronic microscopy of phages," Phage and the origins of molecular biology. Expanded Edition, edited by John Cairns, Gunther Stent and James D. Watson (1992) 63-78.

Genetic recombination in bacteriophages.

In 1969 Delbrück shared the Nobel Prize with A. D. Hershey and S. E. Luria  "for their discoveries concerning the replication mechanism and the genetic structure of viruses."