Skj?t-Arkil H, Clausen RE, Nguyen QH, Wang Y, Zheng Q, Martinez FJ, Hogaboam CM, Han M, Klickstein LB, Larsen MR, Nawrocki A, Leeming DJ, Karsdal MA. Measurement of MMP-9 and -12 degraded elastin (ELM) provides unique information on lung tissue degradation. BMC Pulm Med. 2012 Jul 20; 12:34.