ⅡJapanese Rules and Regulations (rule) article by article commentary

Article 4 (existence of stone)

As far as one stone is next to the street after completion of start, and have sky point; of on a board; wear, and shall exist at point, and stone which there is not of such sky point cannot exist in on a board

Stone which cannot exist on the board
As street where Shiraishi of reference figure 3 was adjacent does not have empty point, we cannot exist on the board.
(reference figure 3)
(reference figure 3)