Examples of telluric line removal leaving no discernible systematic residuals. This statement is quantified in Sect. 4.4. Corrected spectrum (black) and for comparison the original spectrum (thin blue), as well as the spectrum corrected using IRAF (red) in the upper panels normalised for better comparability, as well as the corresponding telluric model in the lower panels of the individual plots: hydrogen lines a) Paschen 9 of CTTS V895 Sco, b) Brackett 13, and c) 10 of CTTS S CrA, as well as d) continuum region of WTTS MV Lup. In the upper panel of subplot d) a PHOENIX model for T_eff = 4800 K (thin black) is also shown (shifted up by 0.1 for clarity).