Complex sentence: In 1831, Sefström of Sweden rediscovered vanadium in a new oxide he found while working with some iron ores and named the element accordingly vanadium; later that same year Friedrich Wöhler confirmed del Río's earlier work.
Split into simpler sentences: In 1831, Sefström of Sweden rediscovered vanadium in a new oxide he found while working with some iron ores. Later that same year Friedrich Wöhler confirmed del Río's earlier work.