An element a of a ring is called a zero-divisor if a ne 0 and ab=0 or ba=0 for some b ne 0; if a is neither 0 nor a zero-divisor, it is said to be regular (see Section 7.1). A non-trivial ring without zero-divisors is called an integral domain; this term is not taken to imply commutativity.

A similar contraption was unveiled in July when some of Diaz’s neighbors attached 55-gallon barrels to a 1951 Chevrolet truck, hooked the drive shaft to a propeller and made their way north. The Coast Guard caught them as they approached South Florida. Some Cuban exiles pressured the U.S. government to let the “truckonauts,” as they called them, enter the country.

[…]one crosses over the Grand Place, on which stands the Cathedral, to the Mozart Place, so called from a statue of the celebrated composer, of whom the Salzburgians are so proud, and thence past the Government Palace to the Cajetan gate, and along the river to the new bridge.

Seventeen brassica vegetables, that is, mustard greens, baby mustard greens, gai choy, baby gai choy, yu choy, yu choy tip, bok choy, baby bok choy, bok choy sum, Taiwan bok choy, Shanghai bok choy, baby Shanghai bok choy, napa and baby napa, rapini broccoli, and turnip greens, were bought in local food stores in Maryland.