Carl Linnaeus, The Lapland Journey, translated by Peter Graves (Edinburgh: Lockharton Press, 1995), p. 160.
Jokkmokk [2], 26/07/1732, ¶870:
26th. A description of an “ackja”. The “ackja” is a form of transport invented by the Lapps. It is dragged along the ground like a sledge and is made of birch wood. The stern, which is oval-shaped and 1 foot high and 1/2 feet wide, is upright but with its lower part sloping slightly inwards. The body is mounted for a little over half its length to a keel, which has 5 planks running lengthwise on each side of it and overlapping each other. It is on this keel that the whole thing rests, not on its sides. All of the planks are 1/2 inches thick, slightly thicker at the upper edge and thinner at the lower edge, so that each plank overlaps the one below it.