Spring conference. British Paper and Board Industry Federation, Technical Division 1981 Spring conference "Engineering contributions to papermaking productivity", 11th/12th March 1981 ... London : [121st conference, British Paper and Board Industry Federation, Technical Division] 1980 Spring conference "Innovation or evolution?" : 12th/13th March 1980 ... Heathrow ; [118th conf., British Paper and Board Industry Federation, Technical Division] 1978 [One hundred and fifteenth spring conference] - [British Paper and Board Industry Federation, Technical Division : London, 15th and 16th March, 1978]