title: Letter: Elemental constitutents of gallstones.
mesh_terms: D002118:Calcium / Q000032:analysis*; D002769:Cholelithiasis / Q000378:metabolism*; D002784:Cholesterol / Q000032:analysis*; D004577:Electron Probe Microanalysis; D006801:Humans; D013058:Mass Spectrometry; D014961:X-Ray Diffraction
chemical_list: D002784:Cholesterol; D002118:Calcium