diff --git a/matlab/tfgm/utils/get_stft_operators.m b/matlab/tfgm/utils/get_stft_operators.m
index 6b41613a4d945b03f259cd237ef99150b8b189a7..a0290bc939eaccb60ec272b22bff095910f04cdc 100644
--- a/matlab/tfgm/utils/get_stft_operators.m
+++ b/matlab/tfgm/utils/get_stft_operators.m
@@ -10,7 +10,10 @@ function [dgt, idgt, varargout] = get_stft_operators(dgt_params, signal_params,
 %     - signal_params: structure which contains the sampling frequency
 %                      as well as the signal length
 %                      see tf_tools/generate_signal_parameters.m
-%     - phase_conv :  Compute a DGT using a frequency-invariant phase.
+%     - phase_conv :  the phase convention 'freqinv' or 'timeinv'
+%                   Compute a DGT using a frequency-invariant phase.
+%       see 'pt' argument in http://ltfat.github.io/doc/gabor/dgtreal.html
+%                           
 %
 % Outputs:
 %     - dgt (handle fucntion) : DGT operator