SNe could be drawn from the same parent distribution (see Table \[SNeindisc\]). In addition, the ratios of the mean values of $|V|/r_{25}$ and $|U|/R_{25}$ in different samples are approximately equal to unity. Thus, after correcting the host galaxies for inclination effects, the distributions of SNe along major ($U/R_{25}$) and minor ($V/r_{25}$) axes turn to be equivalent (see also the standard deviations in Table \[SNeindisc\]). Hereafter, we restrict our analysis to the face-on sample to minimize absorption and projection effects in the discs of galaxies.[^13]

We now adopt the oversimplified model where all SNe are distributed on infinitely thin discs of the host galaxies. While this is a reasonable assumption for SNe within spiral hosts, we shall extend this assumption to S0–S0/a galaxies, for which many find a disc distribution of SNe (e.g. @2008RMxAA..44..103O; for CC and @1999AJ....117.1185H [@2000ApJ...542..588I] for Type Ia SNe).

In this thin-disc approximation, the corrected galactocentric radius (in arcsec) of the SN in the host disc satisfies $$R_{\rm SN}^2 = U^2+\left ({V\over \cos i} \right)^2 \ .\\
\label{RSN}$$ We pay particular attention and discuss the cases when the contribution from the bulge SNe Ia becomes apparent, especially in S0–S0/a hosts.

Influence of bars and bulges on the 