(Translated from original letter)

MASA MADRID , S.A.                      E28100 ALCOBENDAS Madrid (Spain)

September, 17th, 1996

Dear Sir,

With this letter, and attending your request, we want to express our satisfaction after using your additives "rb bertomeu" in our cogeneration [power] plant in Aranjuez, that uses fuel oil No. 1.

We would like to highlight that by using your addtive, we've noticed the following improvements:

- Elimination of corrosion in exhaust valves

- Sludge decrease or combustion residues in valves and turbo compressors

- Sludge decrease to be removed from the purifiers

- Lesser cleaning needs of the purifiers

- Easier purifier cleaning

- Easier water decanting in the fuel oil storage tanks

- Fuel oil consumption decrease per produced KWw/h

- Heavy oil consumption decrease per produced KWw/h

We want to express our satisfaction with the provided Technical Service, in relation with the analytic control of the combustion gas and the general analysis in our plant, which are of great help to keep its performance.

We authorise the use of this letter for reference purposes.