TY  - RPRT
TI  - Density waves in dry granular media falling through a vertical pipe.
AU  - T Raafat
AU  - JP Hulin
AU  - HJ Herrmann
PY  - 1996
DO  - 10.1103/physreve.53.4345
UR  - https://pubmed.ncbi.nlm.nih.gov/9964767/
ID  - 9964767
ER  -