Tob. Reporter, 1986, 113-1, p. 45, ISSN.0361-5693 Device for making grooves in cigarette filters HEANEY R.; REED S.P. US Patent 4,547,253. Brown & Williamson....
Tob. Reporter, 1986, 113-2, p. 66, ISSN.0361-5693 Apparatus for making grooves in cigarette filters NASLUND E.I.; REED S.P. US Patent 4,536,149. Brown & Williamson....