Here is how they work: Cows are trained to follow a series of paths that lead to milking stations.
VOA: special.2009.05.12
But others say music like Lead Belly's would never have become widely known if it wasn't for the work of John Lomax.
VOA: special.2010.01.18
They offer long-term evidence that it can lead to improvements in education,work and health.
VOA: special.2010.03.04
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