The first mention of the octet rule is made by Irving Langmuir, " . . .most stable arrangement of electrons is the octet, that is, a group of 8 electrons like that in the second shell of the neon atom. Any atom with atomic number less than 20, and which has more than 3 electrons in its outside layer tends to take up enough electrons to complete its octet." [JACS 41 868 (1919)].  This is the first rule of electronic structure taught to every chemistry student.