There are number of airlines which will offer connecting flights to Riga. Although flight time will be longer the airline fare will aften be same as for direct flight.
Besides already mentioned airlines we suggest to look at following ones :
SAS - www.flysas.com
KLM - www.klm.com
Lufthansa - www.lufthansa.com
CzechAirlines - www.czechairlines.com
FinnAir - www.finnair.fi
