@phdthesis{OksalaLic,
author = {Oksala, Pekka},
school = {Helsinki University of Technology, Department of Computer Science and Engineering, Digital Systems Laboratory},
title = {Permutaatiomenetelm\"a lomakkeella v\"alitett\"av\"an tiedon salaamiseksi},
type = {Licentiate's thesis},
year = {1990},
}