Although it came out later , it is essentially the introduction to " A Pattern Language " and " The Oregon Experiment " , providing the philosophical background to the Center for Environmental Structure series .
Head entity: the oregon experiment Q7755327 19 20 21
Tail entity: a pattern language Q3602960 13 14 15
Relation (head \u2192 tail): P156
Inverse relation (tail \u2192 head): P155