#if x is in the intersection of 2 basis elements ''B<sub>1</sub>'' and ''B<sub>2</sub>'', then it is in some basis element ''B<sub>3</sub>'', where ''B<sub>3</sub>'' is a subset of ''B<sub>1</sub> ∩ B<sub>2</sub>''. | #if x is in the intersection of 2 basis elements ''B<sub>1</sub>'' and ''B<sub>2</sub>'', then it is in some basis element ''B<sub>3</sub>'', where ''B<sub>3</sub>'' is a subset of ''B<sub>1</sub> ∩ B<sub>2</sub>''. |