That's the randonneur bar [MENTION=185335]Big Block[/MENTION] mentions. 42 cm is their overall width in the drops, though? I think they're more like 38cm at the brake levers.

At any rate, I think it important to note that the current fashion for wider handlebars is (a) a fashion, not necessarily an improvement over the old fashion; and (b) a result of the popularity of mountain biking in the 1980's. By 1990 touring bikes had disappeared from the bike store showroom and any kind of road bikes were getting scarce. When the newly recruited mountain bikers turned to road riding, they wanted bikes that felt more like mountain bikes, with wide handlebars and integrated brake-shift-levers. There's nothing wrong with that; but it is the current fashion, that's all. You can't have that on a 1970 racing bike any more than you can have a Victorian Miniskirt.