"Note that this diffusion coefficient and error estimate are only",
"accurate when the MSD is completely linear between",
"[TT]-beginfit[tt] and [TT]-endfit[tt].[PAR]",
- "Option [TT]-pdb[tt] writes a [TT].pdb[tt] file with the coordinates of the frame",
+ "Option [TT]-pdb[tt] writes a [REF].pdb[ref] file with the coordinates of the frame",
"at time [TT]-tpdb[tt] with in the B-factor field the square root of",
"the diffusion coefficient of the molecule.",
"This option implies option [TT]-mol[tt]."