Doufang refers to folding the long side of rice paper in half and cutting it from the middle. When the long side is folded, it becomes a square, so it is called a square. Because the aspect ratio of rice paper is not absolutely 2: 1, the "square" in calligraphy is not a square. For example:
Three-foot bucket: 55 x 50 cm
Four-foot bucket: 69 x 68 cm
Five-foot bucket: 84 x 77 cm
Six-foot barrel: 97 x 90 cm