Analysis of information sources in references of the Wikipedia article "赫羅圖" in Chinese language version.
The quantities that are easiest to measure... are color and magnitude, so most observers ... refer to the diagram as a 'Color–Magnitude diagram' or 'CMD' rather than an HR diagram.
The quantities that are easiest to measure... are color and magnitude, so most observers ... refer to the diagram as a 'Color–Magnitude diagram' or 'CMD' rather than an HR diagram.