1. Introduction

2. XMM-Newton data
2.1. Observations and data reduction
2.2. Modelled X-ray spectra

3. Optical observations

4. Optical and infrared catalogue identifications
4.1. Cross-correlation method
4.2. Cross-correlation results
4.3. X-ray properties of catalogue counterparts

5. Source classification

6. Stellar population
6.2. Distance
6.3. X-ray luminosity
6.4. Notes on individual sources

7. Properties and characteristics of the sample
7.1. Infrared versus X-ray
7.2. X-ray colours
7.3. log N(>S) - log S

8. Discussion and Conclusions