Feynman on Path Integrals

While looking for an article on the sun's self-absorption of spectral lines, I came across a very early review article by Feynman on path integrals. The article is in Reviews of Modern Physics:

http://rmp.aps.org/abstract/RMP/v20/i2/p367_1

The article is excellent! It starts from basic quantum mechanics and explains path integrals in a very matter-of-fact, pragmatic manner.

Review of Modern Physics carries fairly comprehensive reviews of a variety of physics topics.

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