TY - JOUR PB - American Physical Society ID - 10.1103/Physics.6.2 TI - Leaf Size Fixed by Tree Physics JF - Physics JA - Physics J1 - PHYSICS VL - 6 IS - SP - 2 EP - PY - 2013/01/04/ UR - http://link.aps.org/doi/10.1103/Physics.6.2 A1 - Ball, Philip ER -