Synthesis and crystal structure of La<sub>21</sub>Cr<sub>8−2<i>a</i></sub>Al<sub><i>b</i></sub>Ge<sub>7−<i>b</i></sub>C<sub>12</sub>[<i>a</i>= 0.22 (2) and<i>b</i>= 0.758 (19)]
Acta crystallographica. Section E, Crystallographic communications