@book{ Solr-7354387, title = {Theory Is Forever : Essays Dedicated to Arto Salomaa on the Occasion of His 70th Birthday}, series = {Lecture notes in computer science,}, author = {Karhumäki, Juhani}, editor = {Maurer, Hermann}, editor = {Păun, Gheorghe}, editor = {Rozenberg, Grzegorz}, editor = {SpringerLink (Online service)}, address = {Berlin, Heidelberg}, publisher = {Springer Berlin Heidelberg}, year = {2004}, url = {http://dx.doi.org/10.1007/b98751} }