"Extraterrestrial beings." . . "Cloning." . . "Cloning Fiction." . . . . . "Barton and Nancy are supposed to be minding the store - the pet store, that is. But instead they have left their alien clones, Beta and Gamma, in charge." . . . . "Who let the dogs out?"@en . "Who let the dogs out?" . . . . . "\"Barton and Nancy are supposed to be minding the store--the pet store, that is. But instead they're off trying to win tickets to see their favorite band, Woptic. So who's watching the animals? Their alien clones ...\""@en . . "Twins Barton and Nancy try to use their alien clones to buy tickets for a rock concert, but their plan leads to chaos."@en . "Twins Barton and Nancy try to use their alien clones to buy tickets for a rock concert, but their plan leads to chaos." . . . "Juvenile works" . . . . "Alien clones from outer space"@en . . . "Fiction"@en . "Fiction" . . . . . . . "Who Let the Dogs Out"@en . . . . . . . . . . . . "Brothers and sisters Fiction." . . "Young readers." . . "Clones." . . "Homzie, H.B." . . "Brothers and sisters." . . . . "Twins Fiction." . . "Science fiction." . . "Twins." . .