Shake rum, galliano, crème de Cacao and grapefruit juice with ice. Strain into an ice-filled collins glass. Top with soda water and float the rubus arcticus liqueur. Garnish with lemon peel and berries.
Rubus arcticus, the provinical plant of Norrbotten, Sweden, is also known as arctic raspberry. The liqueur is a simple concoction of sugar, vodka and rubus arcticus berries.
I guess Crème de Framboises could be used as a substitute.