Hi, I have realized that a docstring from the relax_disp code is different in the manual than in the code itself... In "specific_fns/relax_disp.py": ================================== The parameters of these two models are 'fast': [R2, Rex, kex], 'slow': [R2A, kA, dw]. ================================== In the manual (generated using the command: scons user_manual_pdf): ================================== The parameters of these two models are ‘fast’ – [R1 , Rex , kex], ‘slow’ – [R2A, kA, dw]. ================================== As you can see, "R2" is changed for "R1" !!! Moreover, not visible here, but in the manual, "R1" and "Rex" become formatted with subscripts for "1" and "ex", respectively... Does anyone have a clue of what is happening..? Regards, Séb :)