Nonetheless I began to research, at first aimed at finding evidence of SACO's involvement in the Refuse Pit and Bai Mansion prisons, depending mainly on English resources.

There are 27 words or “pigeons” that can start with one of the 26 different English letters or “pigeonholes. ” By the pigeonhole principle, two of the words must start with the same letter.

There are 27 words or "pigeons" that can start with one of the 26 different English letters or "pigeonholes. " By the pigeonhole principle, two of the words must start with the same letter.