Key points are not available for this paper at this time.
The wavelength coverage of 11 of the KPNO spectrophotometric standard stars is extended past 1 micron. The internal agreement is better than a few percent, while the external error at longer wavelengths appears to be 5 percent or better. It is noted that the well-known standard star BD + 28 deg 4211 has a faint red companion.
Massey et al. (Sun,) studied this question.