Determinations of the parallaxes of BD +11 2576 and BD +18 683.

The trigonometric parallaxes of BD +11°2576 and BD +18°683 have been determined with the Zô-sè 40 cm refractor. The authors obtain that the relative parallaxes of BD +11°2576 and BD+18°683 are 0arcsec.1355±0arcsec.0048 and 0arcsec.1255±0arcsec.0052 (internal standard errors), respectively, with the external standard errors, ±0arcsec.0111 and ±0arcsec.0116. The absolute parallaxes of those stars are 0arcsec.1398 and 0arcsec.1283, respectively. The authors also obtain the relative parallaxes 0arcsec.0278±0arcsec.0058 and 0arcsec.0412±0arcsec.0116 (internal standard errors) for BD +11°2574 and AC +19°1513-210 in the same areas. For BD +18°685 they obtain a parallax of 0arcsec.0117±0arcsec.0042.