拠 is one of the most commonly used Japanese kanji, and it also has a lot of special readings in addition to the standard onyomi and kunyomi readings.
ONYOMI 音読み
よ.る yo.ru
KUNYOMI 訓読み
キョ kyo コ ko
Examples
「広辞苑にこう書いてあります」と言って、広辞苑を唯一の拠り所に論陣を張る人がよくいる。There are a lot of people who say, “it says this in Koujien,” and use that dictionary as the only grounds for their argument.