@ARTICLE{
author={Nikacevic Nikola M,Dudukovic Milorad P},
year={2010},
title={Solids Flow Models for Gas - Flowing Solids - Fixed Bed Contactors},
journal={INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING},
volume={8},
number={},
pages={-},
document_type={Article},
} 

@ARTICLE{
author={Nikacevic Nikola M,Petkovska Menka T,Dudukovic Milorad P},
year={2009},
title={Solids flow pattern in gas-flowing solids-fixed bed contactors. Part I Experimental},
journal={CHEMICAL ENGINEERING SCIENCE},
volume={64},
number={10},
pages={2501-2509},
document_type={Article},
} 

@ARTICLE{
author={Nikacevic Nikola M,Petkovska Menka T,Dudukovic Milorad P},
year={2009},
title={Solids flow pattern in gas-flowing solids-fixed bed contactors. Part II Mathematical modeling},
journal={CHEMICAL ENGINEERING SCIENCE},
volume={64},
number={10},
pages={2491-2500},
document_type={Article},
}