1. Introduction  
2. Theoretical Framework  
3. Data Analysis  
3.1. The Dataset  
3.2. The LBG Catalogues  
3.3. Foreground Samples  
3.4. Clustering Measurement  
4. Results  
4.1. Cross-Correlations in Different Magnitude Bins  
4.2. Interpretation of the Observed Signal  
4.3. Optimally Weighted Cross-Correlation Functions  
4.4. Tests for Systematics  
5. Conclusions