Por la compra de 4 unidades iguales o combinadas de los siguientes artículos, GRATIS el de menor importe

{ "offers": [ { "sales_reference": "001018728802127 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801830 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801574 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728802309 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801673 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801855 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728802093 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801616 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801939 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801848 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801863 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728802317 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801186 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801921 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801715 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801624 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801905 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801897 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728801913 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728802549 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728802556 ", "seller": { "identifier": "001" } }, { "sales_reference": "001018728802499 ", "seller": { "identifier": "001" } } ], "subsite": { "identifier": "supermarketHipercorStore", "parent": { "identifier": "supermarket" } }, "query_params": { "centers": { "home_delivery": "0130" }, "is_full_documentation": false, "is_include_offer_availability": true }, "query_list_get_method": "001018728802127___,001018728801830___,001018728801574___,001018728802309___,001018728801673___,001018728801855___,001018728802093___,001018728801616___,001018728801939___,001018728801848___,001018728801863___,001018728802317___,001018728801186___,001018728801921___,001018728801715___,001018728801624___,001018728801905___,001018728801897___,001018728801913___,001018728802549___,001018728802556___,001018728802499___", "delivery_get_method": { "delivery_type": "home_delivery", "center_id": "0130" } }