%0 Journal Article %A Bagchi, Haridas %T Note on the two congruences $ax^2 + by^2 + e \equiv 0$, $ax^2 + by^2 + cz^2 + dw^2 \equiv 0 \: (\text{mod. } p)$, where $p$ is an odd prime and $a \lnot \equiv 0$, $b \lnot \equiv 0$, $c \lnot \equiv 0$, $d \lnot \equiv 0 \: (\text{mod. } p)$ %J Rendiconti del Seminario Matematico della Università di Padova %D 1949 %P 311-315 %V 18 %I Seminario Matematico of the University of Padua %U http://archive.numdam.org/item/RSMUP_1949__18__311_0/ %G en %F RSMUP_1949__18__311_0