Asimov, I. (1968). Pebble in the sky: Science fiction. Sidgwick & Jackson.
芝加哥风格引文Asimov, Isaac. Pebble in the Sky: Science Fiction. London: Sidgwick & Jackson, 1968.
MLA引文Asimov, Isaac. Pebble in the Sky: Science Fiction. Sidgwick & Jackson, 1968.
警告：这些引文格式不一定是100％准确.