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Must contain an initial legend element to summarize details
<p>Josh Gibson holds the all time major
league record for home runs over a career with 962. </p>
<details>
<legend>Gibson's home runs are often not counted because he
played in the Negro Leagues instead of the white
leagues.</legend>
<p>Hank Aaron had only 755. Babe Ruth had 714. Gibson's home
runs are often not counted because he played in the <a
href="http://en.wikipedia.org/wiki/Negro_League_baseball">Negro
Leagues</a> instead of the white leagues. Aaron certainly had to
face tougher pitching in the integrated leagues of his day, but
Ruth faced weaker pitching than Gibson did. In truth, most
records before about 1950 should come with an asterisk.
</p>
</details>