5877 =   28 + 1819 + 1492 +   19 + 116
       + 10 +    7 +    2 + 1802 +  12
       + 31 +   96 +   75 +   45 + 140
       + 23 +    1 +    5 +   14 +  22
       + 3  +    5 +   87 +    6 +  14 + 3
---------------------------------------------------------------
Answers

A. 28
   My letters! all dead paper, mute and white!
   Elizabeth Barrett Browning
   http://www.amherst.edu/~rjyanco/literature/elizabethbarrettbrowning/
      poems/sonnetsfromtheportuguese/mylettersalldeadpapermuteandwhite.html

B. 1819
   An old, mad, blind, despised, and dying king,--
   Percy Bysshe Shelley
   http://www.sonnets.org/shelley.htm#200

C. 1492
   Thou two-faced year, Mother of Change and Fate,
   Emma Lazarus
   http://members.aol.com/sonnetear/lazarus.htm#100

D. 19
   When I consider how my light is spent
   John Milton
   http://eir.library.utoronto.ca/rpo/display/poem1457.html

E. 116
   William Shakespeare
   Let me not to the marriage of true minds
   http://www.allshakespeare.com/sonnets/1036

F. 10
   Death, be not proud, though some have called thee
   John Donne
   http://www.luminarium.org/sevenlit/donne/sonnet10.htm

G. 7
   O Solitude! if I must with thee dwell,
   John Keats
   http://www.portablepoetry.com/poems/john_keats/sonnet_vii.html

H. 2
   Perhaps, long hence, when I have passed away,
   Thomas Hardy
   http://www.sonnets.org/hardy.htm#002

I. 1802
   MILTON! thou shouldst be living at this hour:
   William Wordsworth
   http://www.bartleby.com/101/524.html

J. 12
   Full woman, fleshly apple, hot moon,
   Pablo Neruda
   http://www-personal.umich.edu/~pfa/poemquot/neruda12.html

K. 31
   Oh, oh you will be sorry for that word!
   Edna St. Vincent Millay
   http://www.ksu.edu/english/janette/installations/Jill/sonnet.htm

L. 96
   It will seem strange, no more this range on range
   John Berryman
   http://plagiarist.com/poetry/9114/

M. 75
   One day I wrote her name upon the strand,
   Edmund Spenser
   http://www.xs4all.nl/~josvg/cits/poem/es.html

N. 45
   Care-charmer Sleep, son of the sable Night
   Samuel Daniel
   http://www.luminarium.org/renlit/delia45.htm

O. 140
   Love, who rules my thinking as his empire
   Petrarch
   http://www.polyamory.org/~howard/Poetry/petrarch_140.html

P. 23
   I stood where Love in brimming armfuls bore
   Dante Gabriel Rossetti
   http://www.alsintl.com/poetry/lovesbaubles.htm

Q. 1
   Caesar, when that the traitor of Egypt,
   Thomas Wyatt
   http://www.shakespeares-sonnets.com/Wyatt2.htm

R. 5
   A goiter it seems I got from this backward craning
   Michelangelo Buonarroti
   http://www.harvardmagazine.com/issues/mj97/poetry.html

   [John Frederick Nims has translated all of Michelangelo's 80 completed
   and 40 unfinished sonnets; this one is numbered ifth among the artist's
   poems. A sonetto caudato ("sonnet with tail," he six additional lines),
   it dates to 1509 or 1510, while Michelangelo was at work on the
   Sistine Chapel.]

S. 14
   If he from Heav'n that filch'd that living fire
   Michael Drayton
   http://www.eecs.harvard.edu/~keith/poems/idea14.html

T. 22
   He died of "Stranger's Fever" when his youth
   Amy Lowell
   http://users.telenet.be/gaston.d.haese/lowell_sonnets.html

U. 3
   A graceless doom it seems that bids us grieve:
   Algernon Charles Swinburne
   http://eir.library.utoronto.ca/rpo/display/poem2100.html

V. 5
   If I should die, think only this of me:
   Ruperlettert Brooke
   http://members.aol.com/ericblomqu/wwi.htm

W. 87
   THE earth, with thunder torn, with fire blasted,
   Fulke Greville
   http://www.luminarium.org/renlit/caelica87.htm

X. 6
   O star of morning and of liberty!
   Henry Wadsworth Longfellow
   http://www.sonnets.org/longfell.htm#505

Y. 14
   We share the cycle of flower, grapeleaf, fruit.
   Rainer Maria Rilke
   http://www.polyamory.org/~howard/Poetry/rilke_orpheusI14.html

Z. 3
   The Sonnet is a world, where feelings caught
   John Addington Symonds
   http://www.sonnets.org/symonds.htm#100