Henry Gordon Rice (1953). "Classes of Recursively Enumerable Sets and Their Decision Problems". Transactions of the American Mathematical Society (American Mathematical Society) 74 (2): 358–366. JSTOR1990888. doi:10.2307/1990888.
jstor.org
Henry Gordon Rice (1953). "Classes of Recursively Enumerable Sets and Their Decision Problems". Transactions of the American Mathematical Society (American Mathematical Society) 74 (2): 358–366. JSTOR1990888. doi:10.2307/1990888.