Publisher Correction: Laser spectroscopy of the $$^2S_{1/2}{-}^2P_{{1}/2}$$ 2 S 1 / 2 - 2 P 1 / 2 , $$^2P_{3/2}$$ 2 P 3 / 2 transitions in stored and cooled relativistic $${\text{C}}^{3+}$$ C 3 + ions - D. Winzen (Nature Portfolio, 2021)