Không rõ. (1979). Computer and Intractability. NOTNXB.
Trích dẫn kiểu ChicagoKhông rõ. Computer and Intractability. NOTNXB, 1979.
MLA引文Không rõ. Computer and Intractability. NOTNXB, 1979.
警告：這些引文格式不一定是100％准確.
APA引文
Không rõ. (1979). Computer and Intractability. NOTNXB.
Trích dẫn kiểu ChicagoKhông rõ. Computer and Intractability. NOTNXB, 1979.
MLA引文Không rõ. Computer and Intractability. NOTNXB, 1979.