1 Introduction

This series of papers aims mainly at improving the accuracy of equatorial galaxy coordinates in order to facilitate the cross-identification with the very large catalogue we built from the Digitized Sky Survey using an automatic galaxy recognition program (Paturel et al. 2000). Nevertheless, it is also important to enter new galaxies well identified visually, especially when they are either close to large galaxies or when they have a low surface brightness. Indeed, these two characteristics make difficult an automatic recognition.

This paper presents two independent sections, both aiming at improvement of equatorial coordinates of galaxies. In Sect. 2 we describe the catalogue of companions of UGC galaxies. Most of these galaxies are not yet entered in large databases. Then, in Sect. 3 we give a short description of additional 13935 coordinate measurements. These measurements are performed in a way similar to the one described in our previous paper (Paturel et al. 1999; Paper II).