Given the input sentence, please extract the subject and object containing a certain relation in the sentence according to the following relation types, in the format of "relation1: word1, word2; relation2: word3, word4". Relations include: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

In 2014, the Buick line sold 919,582 vehicles in the country – almost four times higher than the 228,963 units of Buick sold in the U.S. General Motors believes that its sales volume for Buick in the U.S will not be large enough to justify the establishment of a plant in U.S.

Answer: parent_organization: Buick, General Motors; owned_by: Buick, General Motors