{TAIL ~ The enclosure member} is permeable to at least one fluid in the subterranean formation or injected with the capsules such that upon sufficient exposure to {HEAD ~ the fluid}, the capsules rupture, thereby releasing the breaker to the formation 
{ TAIL ~ The enclosure member } is permeable to at least one fluid in the subterranean formation or injected with the capsules such that upon sufficient exposure to { HEAD ~ the fluid } , the capsules rupture , thereby releasing the breaker to the formation
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH