1 INTRODUCTION

2 SOURCE SELECTION AND OBSERVATIONS  
2.1 Observations in the 20 GHz band  
2.2 Lower-frequency observations

3 DATA REDUCTION

4 POLARISATION OF EXTENDED SOURCES

5 DATA ANALYSIS  
5.1 Spectral properties of the sample  
5.2 Fractional polarisation

6 SOURCE COUNTS IN POLARISATION

7 POLARISATION CALIBRATORS AT MILLIMETRIC WAVELENGTHS

8 CONCLUSIONS