Sei [ a , b ] ⊂ R {\displaystyle [a,b]\subset \mathbb {R} } ein Intervall.
http://books.google.de/books?id=aFDWuZZslUUC&pg=PA1260&lpg=PA1260&dq=encyclopedia+of+math+green+function&source=bl&ots=4phVqxG8hQ&sig=3pquaxVZuobEflP6b_oi4OwyPaA&hl=de&sa=X&ei=lZpKU8f0BoKMtQaa6YGwDA&ved=0CEoQ6AEwAw#v=onepage&q=encyclopedia%20of%20math%20green%20function&f=false
http://www.encyclopediaofmath.org/index.php/Green_function#Green_function_for_ordinary_differential_equations.
![{\displaystyle [a,b]\subset \mathbb {R} }](https://wikimedia.org/api/rest_v1/media/math/render/svg/a659536067aaaac2db1c44613a09a715f0cf7246)