Discret ization of the poisson Problem in IR: Theory and Implementation April7&9,2003￾✂✁☎✄✝✆✟✞✡✠☞☛✌✁☎✍✏✎✏☛✌✁✒✑✔✓✕✑✗✖✘☛✝✙✚✠✜✛✢✑✔✁☎✄✣✄✌✑✔✓ ✛✤✞✡✑✔✥✧✦✒✠✩★ ✁☎✓✕✪✬✫✮✭✰✯✲✱✳✙✚✠✟✑✴✞✶✵✷✎✸✓✧✹ ✪✺★✼✻✧✦✒✠✟★✽✠✰✓✾☛✿✎❀☛✝✁✒✑✔✓ ❁✧❂✌❃❅❄❇❆❉❈✘❊●❋✌❍✰■✶❏❑❏✶▲