How to write image caption in bootstrap theme


I am trying to write image caption using the below html and it did not work for me. I am trying to put the image caption under the image. Am I using correct classes? I also searched in getbootstrap css page. I could not find anything.

<figure class="figure"><img class = "block_img img-responsive" src="/sites/default/files/baltimore-md.jpeg" alt="local house -buyers - sell your house" /> <figcaption class="figure-caption">A caption for the above image.</figcaption></figure>

Please advise.

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