Google Articles Background Research Documents: [dg ids="135480,135481,135482,135483,135484,135485,135486,135487,135488,135489,135490,135491,135492,135493,135494,135495,135496,135497,135498,135499,135500,135501,135502,135503,135504,135505,135506,135507,135508,135509,135510,135511,135512,135513,135514,135515,135516,135517,135518,135519,135520,135521,135522,135523,135524,135525,135526,135527,135528,135529,135530,135531,135532,135533,135534,135535,135536,135537,135538,135539,135540,135541,135542,135543,135544,135545,135546,135547,135548,135549,135550,135551,135552,135553,135554,135555,135556,135557,135558,135559,135560,135561,135562,135563,135564,135565,135566,135567,135568,135569,135570,135571,135572,135573,135574,135575,135576,135577,135578,135579,135580,135581,135582,135583,135584,135585,135586,135587,135588,135589,135590,135591,135592,135593,135594,135595,135596,135597,135598,135599,135600,135601,135602,135603,135604,135605,135606,135607,135608,135609,135610,135611,135612,135613,135614,135615,135616,135617,135618,135619,135620,135621,135622,135623,135624,135625,135626,135627,135628,135629,135630,135631,135632,135633,135634,135635,135636,135637,135638,135639,135640,135641,135642,135643,135644,135645,135646,135647,135648,135649,135650,135651,135652,135653,135654,135655,135656,135657,135658,135659,135660,135661,135662,135663,135664,135665,135666,135667,135668,135669,135670,135671,135672,135673,135674,135675,135676,135677,135678,135679,135680,135681,135682,135683,135684,135685,135686,135687,135688,135689,135690,135691,135692,135693,135694,135695,135696,135697,135698,135699,135700,135701,135702,135703,135704,135705,135706,135707,135708,135709,135710,135711,135712,135713,135714,135715,135716,135717,135718,135719,135720,135721,135722,135723,135724,135725,135726,135727,135728,135729,135730,135731,135732,135733,135734,135735,135736,135737,135738,135739,135740,135741,135742,135743,135744,135745,135746,135747,135748,135749,135750,135751,135752,135753,135754,135755,135756,135757"]