. "http://encyclopedia2.thefreedictionary.com/migration+area"^^ . . . . . . "http://www.iso.org/iso/catalogue_detail?csnumber=31895"^^ . . "\"Migration Area\" is the sum of the slowing-down area from fission energy to thermal energy and the diffusion area for thermal neutrons." . "M^2" . "Migration Area"@en . . . . . . . . . . . . . . .