"The Core trade was the interstellar trade among the core worlds of the Solarian League. It was considered to be very lucrative. Michael Parmley and Elfride Butre tried to establish a freight company to compete in it in the 19th Century PD, but failed. (CS2)"@en . "The Core trade was the interstellar trade among the core worlds of the Solarian League. It was considered to be very lucrative. Michael Parmley and Elfride Butre tried to establish a freight company to compete in it in the 19th Century PD, but failed. (CS2)"@en . . "Core trade"@en . . .