I want to know if The Three Laws of Robotics are explicitly defined in one of the Asimov's robot stories. In which one? I am asking this question because I remember reading something about the laws being compiled by his editor.
According to the Wikipedia article on the Three Laws of Robotics:
The rules are introduced in his 1942 short story Runaround although they were foreshadowed in a few earlier stories.
That 1942 story is available at the Internet Archive; the three laws are on p. 100, col. 1.