title: Polymorphism in sedimentation velocity and density of lambda bacteriophage.
mesh_terms: D001435:Bacteriophages / Q000145:classification*; D002586:Cesium; D003090:Coliphages / Q000302:isolation & purification*; D003720:Densitometry; D004926:Escherichia coli; D005827:Genetics, Microbial; D008722:Methods; D010641:Phenotype; D011110:Polymorphism, Genetic; D013997:Time Factors; D014461:Ultracentrifugation
chemical_list: D002586:Cesium