Spatial distribution of the H₂O (circle) maser and SiO (square) maser spots toward NML Cyg from the fifth epoch observation. Each maser spot is represented by a filled circle or square whose area is proportional to the logarithm of the flux density. The position of the central star is indicated by a star (see the text in Sect. 3.3). The color bar denotes the V_LSR range from −25 to 25 km s^-1 of the maser features. The reference H₂O maser spot is located at (0, 0) mas. (This figure is available in color in electronic form.)