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2. Formation of single-ovum twins;Streeter;Bull Johns Hopkins Hosp (Baltimore),1919
3. The morphological theory of monochorionic twins as illustrated by a series of supposed early twin embryos of the pig;Corner;Bull Johns Hopkins Hosp (Baltimore),1922
4. Surgery on conjoined (Siamese) twins;Kiesewetter;Surgery,1966
5. Shandling B: Hospital for Sick Children, Toronto, Ontario. Personal communication