The man who found a copy of Action Comics #1 stuffed inside the walls of a house he was renovating has unearthed a second rare Superman comic book.

Action Comics #1 holds the world record for any comic book, after selling for $2.1m in 2011

The 1938 issue of Action Comics #1, which is perhaps the most famous comic in the world due to its first appearance of Superman, sold for $175,000 in June.

Now, the lucky renovator has discovered another rare Superman issue, but remains uncertain of its value.

"We know it's a Superman issue, we just don't know what issue," David Gonzalez, 35, told ABC News."I know it's the one [of Superman] fighting with the dinosaurs."

It is likely that it is issue #4 from the eponymous series that was launched in 1939, which is generally worth between $500 and $5,000 depending on its condition.

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