Gustav Kirchhoff was born on March 12, 1824 and died on October 17, 1887. Gustav Kirchhoff would have been 63 years old at the time of death or 188 years old today.
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Gustav Nezval was born on November 18, 1907 and died on September 17, 1998. Gustav Nezval would have been 90 years old at the time of death or 104 years old today.
Peter Gustav Dirichlet was born on February 13, 1805 and died on May 5, 1859. Peter Gustav Dirichlet would have been 54 years old at the time of death or 207 years old today.