SELECT id, ort, fachwort, (
6368 * SQRT(2*(1-cos(RADIANS(lng)) *
cos(0.20572876571665) * (sin(RADIANS(lat)) *
sin(0.8397224090304) + cos(RADIANS(lat)) *
cos(0.8397224090304)) - sin(RADIANS(lng)) * sin(0.20572876571665)))) AS entfernung
FROM literatur WHERE
6368 * SQRT(2*(1-cos(RADIANS(lng)) *
cos(0.20572876571665) * (sin(RADIANS(lat)) *
sin(0.8397224090304) + cos(RADIANS(lat)) *
cos(0.8397224090304)) - sin(RADIANS(lng)) * sin(0.20572876571665))) <= 25
ORDER BY entfernung