Sutherland G R, Leonard P
Hum Genet. 1979;53(1):29-30. doi: 10.1007/BF00289446.
The chromosomal gaps associated with fragile sites at 2q11, 10q23, 11q13, 16q22, 20p11 and Xq27 do not stain with silver nitrate as do NOR regions of the acrocentric chromosomes.