Koshida, ShintaroYoshii, YuzuruKobayashi, YukiyasuMinezaki, TakeoSakata, YuSugawara, ShotaEnya, KeigoSuganuma, MasahiroTomita, HiroyukiAoki, TsutomuPeterson, Bruce2015-12-080004-637Xhttp://hdl.handle.net/1885/34068Long-term optical and near-infrared monitoring observations for a type 1 active galactic nucleus (AGN) NGC4151 were carried out for six years from 2001 to 2006 by using the MAGNUM telescope, and delayed response of flux variations in the K(2.2 μm) band tKeywords: Dust, extinction; Galaxies: active; Galaxies: individual (NGC 4151); Galaxies: Seyfert; Infrared: galaxies200910.1088/0004-637X/700/2/L1092016-02-24