To Purchase this Sefer 
Every Jew is obligated to give at least two presents to two paupers, [one present to each pauper].
Why is a blessing not recited before performing the Mitzvah of Matanos Laevyonim?
As it is possible the pauper will refuse to accept the gift, hence the gift must first be given to the pauper, and being it was already given one can no longer say a blessing. Alternatively it is because we do not say a blessing over Mitzvos that are done between man and his fellow.