Zhekov, Z. .; Kalev, K. . A SPECIAL CASE OF CALCULATION OF OPTICAL SYSTEM FOR A COLLIMATOR WITH AN ANFOCAL ACHROMATIC COLLIMATOR: A SPECIAL CASE OF CALCULATION OF OPTICAL SYSTEM FOR A COLLIMATOR WITH AN ANFOCAL ACHROMATIC COLLIMATOR. JSAR 2023, 18, 12-16.