Robert Recorde, The designer ofwel the equals sign, introduced plus and minus to Britain in 1557 in The Whetstone of Witte:[14] "There be other twee signes in often use ofwel which the first is made thus + and betokeneth more: the other is thus made − and betokeneth lesse." El https://writeablog.net/papersnow5/overwegingen-om-te-weten-over-wat-is-wrapfolie-wiki