• Listing assertions made by each side before today's UK referendum on the alternative vote system, we said: "AV is used for Scottish local councils, in Northern Ireland, and the Republic of Ireland. US cities elect mayors by AV" (How valid are the two campaigns' claims? 4 May, page 9). What we should have said was: the Republic of Ireland uses AV in presidential elections and parliamentary byelections. At local level in the United Kingdom, AV is used in byelections for Scotland's and Northern Ireland's local councils. A handful of US cities use AV in local votes.
• A commentary on the outcome of Canada's national election gave Calgary, Alberta, as the birthplace of the prime minister, Stephen Harper. Alberta was, rather, the province that became his political base after he left his home town – Toronto – to complete university studies in the western province (Canada's cold new dawn, 4 May, page 30).
• A report on a Paris competition for best baguette gave the weight for submitted loaves as between 240g and 310g, and then went on to quote the president of the bakers' union as saying the salt content should not exceed 18g. To clarify: that was per kilo of flour. Meaning that in a 250g loaf the salt would be about 4.5g or just under a teaspoon (Battle of the baguettes..., 4 May, page 23).