Estimated Friends:
Somebody can help me for to obtain a copy of the next technical papers:

1 - Tower Packing and Packed Tower Design by M. Leva U.S. Stoneware

2 - Pressure Drop Prediction with New Correlation by Robbins Chem. Eng. Prog. 1991

3 - Selecting the Proper Distillation Column Packing by Eckert J. S. Chem. Eng. Prog. 1970

4 - Packed Distillation Column Design by Strigle & Rukovena Chem. Eng. Prog. 1979

5 - Packed Column Analysis and Design by Billet

THANKS IN ADVANCE