frequencies of strong and unblended transitions were determined with a $1\sigma$ random uncertainty of 0.002[cm$^{-1}$]{}, and weak and blended lines with somewhat greater uncertainty. The absolute accuracy of the frequency measurements then varies between 0.003 and 0.03[cm$^{-1}$]{} for the strongest and weakest/blended lines, respectively.

![High resolution emission spectra of the [$^{13}$C$^{16}$O]{} [B$^1\Sigma^+-$A$^1\Pi$]{} $(0,0)$, [B$^1\Sigma^+-$e$^3\Sigma^-$]{} $(0,1)$, and [B$^1\Sigma^+-$d$^3\!\Delta$]{} $(0,4)$ systems recorded with the VIS-FTS setup with an instrumental resolution of 0.018 [cm$^{-1}$]{}. The estimated accuracy of the frequency scale calibration is 0.003 [cm$^{-1}$]{}. Absolute accuracies of the frequency measurements vary between 0.003 [cm$^{-1}$]{} for the strongest lines and 0.03 [cm$^{-1}$]{} for the weakest or most blended. The composition ratio of the gas used in the experiment was $^{13}$C$^{16}$O : $^{13}$C$^{17}$O = 0.43 : 1.[]{data-label="fig:FTBXspec"}](13C16O_BA00.eps){width="\textwidth"}

Transition frequencies for the [B$^1\Sigma^+-$A$^1\Pi$]{}$(0,0)$ band of $^{13}$C$^{16}$O are listed in Table \[FTandlasertransition\], and frequencies of the perturber lines are listed in Table \[FT-pert\].

[c@l@l@l@l@l@l@l@l]{}\
& &\
[$J$]{}& & & & & & & &\
\
0 & & & & & & & 64790.51&\
1 & 64754.157& 64754.170& 64789.84& & & 64793.48& 64796.52&\
2 & 64760.184& 64760.235& 64792.28& & & 64798.36& 64803.77&\
3 & 64769.202& 64769.32 & 64797.25& & & 64805.67& 64813.43&\
4 & 64781.16 & 