1. Bennet, C. W.: Studies of dodder transmission of plant viruses. Phytopathology34, 905–932 (1944).
2. Gardiner, W.: On the continuity of the protoplasm through the walls of vegetable cells. Arb. Würzburger bot. Inst.3, 52–87 (1888).
3. ——: The histology of the cell wall with special reference to the mode of connexion of cells. Proc. Roy. Soc. Lond.62, 100–112 (1898).
4. Henckel, P. A.: The adaptive significance of dormancy in plants. Referat auf dem internat. Bot. Kongr. Stockholm 1950.
5. Jungers, V.: Recherches sur les plasmodesmes chez les végétaux. I. Cellule40, 7–82 (1930).