The hanbali jurist, Awn ad-Din Ibn Hubayra al-Baghdadi al-Hanbali (d. 560H) writes in his book اختلاف الأئمة العلماء, in which he mentions the agreements and disagreement between the scholars :
وَقَالَ مَالك وَالشَّافِعِيّ: يضعهما تَحت صَدره وَفَوق سرته.
وَعَن أَحْمد ثَلَاث رِوَايَات أشهرها كمذهب أبي حنيفَة وَهِي الَّتِي اخْتَارَهَا الْخرقِيّ، وَالثَّانيَِة كمذهب مَالك وَالشَّافِعِيّ. وَالثَّالِثَة التَّخْيِير بَينهمَا وأنهما فِي الْفَضِيلَة سَوَاء.
Abu Hanifa said: places them below the navel.
Malik and Shafii said: places them below the chest and above the navel
And Ahmed (bin Hanbal) there are three attributions: The best known is that of the madhab of Abu Hanifa and this was chosen by Al-Kharqi, the second is that of the madhab of Malik and Shafi. And the third is that there is no constraints in (choosing) either of this and that both are virtuous.
For statements of other hanbali scholars on this issue, see: The Hanbali Opinion on Where to Place the Hands in Salah