\begin{table}%t1 \caption{\label{tab:data1}Optical and infrared observations of EX~Lup collected from the literature, obtained in its quiescent periods.} \small %\centerline { \begin{tabular}{l l l c} \hline \hline $\lambda$ [$\mu$m] &Julian date & Magnitude & Reference\\ \hline 0.36 ($U$) &2~443~349.545 &$14.21$ &1 \\ &2~443~349.572 &$14.2$ &1 \\ &2~443~349.681 &$14.23$ &1 \\ &2~443~349.717 &$14.25$ &1 \\ &2~443~349.728 &$14.28$ &1 \\ &2~443~350.653 &$14.22$ &1 \\ &2~443~353.659 &$14.13$ &1 \\ &2~443~895.85 &$14.52$ &2 \\ \hline 0.44 ($B$) &2~443~349.545 &$14.33$ &1 \\ &2~443~349.572 &$14.36$ &1 \\ &2~443~349.681 &$14.24$ &1 \\ &2~443~349.717 &$14.36$ &1 \\ &2~443~349.728 &$14.33$ &1 \\ &2~443~350.653 &$14.20$ &1 \\ &2~443~353.659 &$14.07$ &1 \\ &2~443~894.85 &$14.52$ &2 \\ &2~443~895.85 &$14.42$ &2 \\ &2~448~896 &$14.21$ &3 \\ \hline 0.55 ($V$) &2~443~349.545 &$13.13$ &1 \\ &2~443~349.572 &$13.19$ &1 \\ &2~443~349.681 &$13.27$ &1 \\ &2~443~349.717 &$13.27$ &1 \\ &2~443~349.728 &$13.21$ &1 \\ &2~443~350.653 &$13.14$ &1 \\ &2~443~353.659 &$13.22$ &1 \\ &2~443~894.85 &$13.20$ &2 \\ &2~443~895.85 &$13.22$ &2 \\ &2~448~896 &$13.03$ &3 \\ \hline 0.64 ($R$) &2~448~896 &$12.15$ &3 \\ \hline 0.79 ($I$) &2~451~295.81 &$11.109$&4 \\ \hline 1.25 ($J$) &2~441~474 &$9.76$ &5 \\ 1.25 ($J$) &2~445~075 &$9.92$ &6 \\ 1.235($J$) &2~451~314.781 &$9.728$ &7 \\ 1.221($J$) &2~451~295.81 &$9.92$ &4 \\ \hline 1.65 ($H$) &2~441~474 & $9.04$ &5 \\ 1.65 ($H$) &2~445~075 &$9.11$ &6 \\ 1.662($H$) &2~451~314.781 &$8.958$ &7 \\ \hline 2.2 ($K$) &2~441~474 &$8.82$ &5 \\ 2.2 ($K$) & 2~445~075 &$8.78$ &6 \\ 2.159 ($K_{\rm s}$)& 2~451~314.781&$8.496$ &7 \\ 2.144 ($K_{\rm s}$)& 2~451~295.81 &$8.82$ &4 \\ \hline 3.4 ($L$) & 2~441~474 &$\ge$$8.7$&5 \\ 3.4 ($L$) & 2~445~075 &$8.05$ &6 \\ \hline 4.8 ($M$) & 2~445~075 &$7.54$ &6 \\ \hline \end{tabular}} \smallskip References: (1) \citet{ref:bastian_1979}; (2) \citet{ref:mundt_1980}; (3) \citet{ref:herbig_1992}; (4) The DENIS database (DENIS Consortium 2005); (5) \citet{ref:glass_1974}; (6) \citet{ref:hughes_1994}; (7) 2MASS All-Sky Catalog of Point Sources \citep{ref:cutri_2003}. \end{table}