السلام عليكم
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الرابط
http://www.chem.ox.ac.uk/icl/heyes/structure_of_solids/Strucsol.html
بالتوفيق...
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الرابط
http://www.chem.ox.ac.uk/icl/heyes/structure_of_solids/Strucsol.html
بالتوفيق...