function countChoices(obj) {
max = 20; // max. number allowed at a time
DavidBaldacci = obj.form.DavidBaldacci.checked;
NevadaBarr = obj.form.NevadaBarr.checked;
ElizabethBerg = obj.form.ElizabethBerg.checked;
MaeveBinchy = obj.form.MaeveBinchy.checked;
BarbaraTaylorBradford = obj.form.BarbaraTaylorBradford.checked;
LilianJacksonBraun = obj.form.LilianJacksonBraun.checked;
DanBrown = obj.form.DanBrown.checked;
SandraBrown = obj.form.SandraBrown.checked;
JamesLeeBurke = obj.form.JamesLeeBurke.checked;
LeeChild = obj.form.LeeChild.checked;
TomClancy = obj.form.TomClancy.checked;
MaryHigginsClark = obj.form.MaryHigginsClark.checked;
HarlanCoben = obj.form.HarlanCoben.checked;
MichaelConnelly = obj.form.MichaelConnelly.checked;
PatConroy = obj.form.PatConroy.checked;
RobinCook = obj.form.RobinCook.checked;
PatriciaCornwell = obj.form.PatriciaCornwell.checked;
CatherineCoulter = obj.form.CatherineCoulter.checked;
RobertCrais = obj.form.RobertCrais.checked;
MichaelCrichton = obj.form.MichaelCrichton.checked;
CliveCussler = obj.form.CliveCussler.checked;
DianeMottDavidson = obj.form.DianeMottDavidson.checked;
JeffDeaver = obj.form.JeffDeaver.checked;
BarbaraDelinsky = obj.form.BarbaraDelinsky.checked;
NelsonDeMille = obj.form.NelsonDeMille.checked;
JudeDeveraux = obj.form.JudeDeveraux.checked;
JanetEvanovich = obj.form.JanetEvanovich.checked;
KenFollett = obj.form.KenFollett.checked;
JulieGarwood = obj.form.JulieGarwood.checked;
ElizabethGeorge = obj.form.ElizabethGeorge.checked;
TessGerritsen = obj.form.TessGerritsen.checked;
SueGrafton = obj.form.SueGrafton.checked;
JohnGrisham = obj.form.JohnGrisham.checked;
KristinHannah = obj.form.KristinHannah.checked;
CarlHiaasen = obj.form.CarlHiaasen.checked;
JackHiggins = obj.form.JackHiggins.checked;
TonyHillerman = obj.form.TonyHillerman.checked;
TamiHoag = obj.form.TamiHoag.checked;
JohnIrving = obj.form.JohnIrving.checked;
SusanIsaacs = obj.form.SusanIsaacs.checked;
IrisJohansen = obj.form.IrisJohansen.checked;
JanKaron = obj.form.JanKaron.checked;
FayeKellerman = obj.form.FayeKellerman.checked;
JonathanKellerman = obj.form.JonathanKellerman.checked;
BarbaraKingsolver = obj.form.BarbaraKingsolver.checked;
DeanKoontz = obj.form.DeanKoontz.checked;
JayneAnnKrentz = obj.form.JayneAnnKrentz.checked;
DennisLehane = obj.form.DennisLehane.checked;
ElizabethLowell = obj.form.ElizabethLowell.checked;
PhillipMargolin = obj.form.PhillipMargolin.checked;
SteveMartini = obj.form.SteveMartini.checked;
EdMcBain = obj.form.EdMcBain.checked;
LarryMcMurtry = obj.form.LarryMcMurtry.checked;
BradMeltzer = obj.form.BradMeltzer.checked;
MarciaMuller = obj.form.MarciaMuller.checked;
SaraParetsky = obj.form.SaraParetsky.checked;
RobertParker = obj.form.RobertParker.checked;
JamesPatterson = obj.form.JamesPatterson.checked;
RichardNorthPatterson = obj.form.RichardNorthPatterson.checked;
AnnePerry = obj.form.AnnePerry.checked;
BelvaPlain = obj.form.BelvaPlain.checked;
RosamundePlicher = obj.form.RosamundePlicher.checked;
AmandaQuick = obj.form.AmandaQuick.checked;
AnnaQuindlen = obj.form.AnnaQuindlen.checked;
KathyReichs = obj.form.KathyReichs.checked;
NoraRoberts = obj.form.NoraRoberts.checked;
JohnSandford = obj.form.JohnSandford.checked;
JohnSaul = obj.form.JohnSaul.checked;
LisaScottoline = obj.form.LisaScottoline.checked;
AnitaShreve = obj.form.AnitaShreve.checked;
AnnRiversSiddons = obj.form.AnnRiversSiddons.checked;
AlexanderMcCallSmith = obj.form.AlexanderMcCallSmith.checked;
NicholasSparks = obj.form.NicholasSparks.checked;
DanielleSteel = obj.form.DanielleSteel.checked;
AmyTan = obj.form.AmyTan.checked;
ScottTurow = obj.form.ScottTurow.checked;
AnnTyler = obj.form.AnnTyler.checked;
StuartWoods = obj.form.StuartWoods.checked;

count = (DavidBaldacci ? 1 : 0) + (NevadaBarr ? 1 : 0) + (ElizabethBerg ? 1 : 0) + (MaeveBinchy ? 1 : 0) + (BarbaraTaylorBradford ? 1 : 0) + (LilianJacksonBraun ? 1 : 0) + (DanBrown ? 1 : 0) + (SandraBrown ? 1 : 0) + (JamesLeeBurke ? 1 : 0) + (LeeChild ? 1 : 0) + (TomClancy ? 1 : 0) + (MaryHigginsClark ? 1 : 0) + (HarlanCoben ? 1 : 0) + (MichaelConnelly ? 1 : 0) + (PatConroy ? 1 : 0) + (RobinCook ? 1 : 0) + (PatriciaCornwell ? 1 : 0) + (CatherineCoulter ? 1 : 0) + (RobertCrais ? 1 : 0) + (MichaelCrichton ? 1 : 0) + (CliveCussler ? 1 : 0) + (DianeMottDavidson ? 1 : 0) + (JeffDeaver ? 1 : 0) + (BarbaraDelinsky ? 1 : 0) + (NelsonDeMille ? 1 : 0) + (JudeDeveraux ? 1 : 0) + (JanetEvanovich ? 1 : 0) + (KenFollett ? 1 : 0) + (JulieGarwood ? 1 : 0) + (ElizabethGeorge ? 1 : 0) + (TessGerritsen ? 1 : 0) + (SueGrafton ? 1 : 0) + (JohnGrisham ? 1 : 0) + (KristinHannah ? 1 : 0) + (CarlHiaasen ? 1 : 0) + (JackHiggins ? 1 : 0) + (TonyHillerman ? 1 : 0) + (TamiHoag ? 1 : 0) + (JohnIrving ? 1 : 0) + (SusanIsaacs ? 1 : 0) + (IrisJohansen ? 1 : 0) + (JanKaron ? 1 : 0) + (FayeKellerman ? 1 : 0) + (JonathanKellerman ? 1 : 0) + (BarbaraKingsolver ? 1 : 0) + (DeanKoontz ? 1 : 0) + (JayneAnnKrentz ? 1 : 0) + (DennisLehane ? 1 : 0) + (ElizabethLowell ? 1 : 0) + (PhillipMargolin ? 1 : 0) + (SteveMartini ? 1 : 0) + (EdMcBain ? 1 : 0) + (LarryMcMurtry ? 1 : 0) + (BradMeltzer ? 1 : 0) + (MarciaMuller ? 1 : 0) + (SaraParetsky ? 1 : 0) + (RobertParker ? 1 : 0) + (JamesPatterson ? 1 : 0) + (RichardNorthPatterson ? 1 : 0) + (AnnePerry ? 1 : 0) + (BelvaPlain ? 1 : 0) + (RosamundePlicher ? 1 : 0) + (AmandaQuick ? 1 : 0) + (AnnaQuindlen ? 1 : 0) + (KathyReichs ? 1 : 0) + (NoraRoberts ? 1 : 0) + (JohnSandford ? 1 : 0) + (JohnSaul ? 1 : 0) + (LisaScottoline ? 1 : 0) + (AnitaShreve ? 1 : 0) + (AnnRiversSiddons ? 1 : 0) + (AlexanderMcCallSmith ? 1 : 0) + (NicholasSparks ? 1 : 0) + (DanielleSteel ? 1 : 0) + (AmyTan ? 1 : 0) + (ScottTurow ? 1 : 0) + (AnnTyler ? 1 : 0) + (StuartWoods ? 1 : 0);

if (count > max) {
alert("Oops!  You can only choose up to " + max + " choices! \nUncheck an option if you want to pick another.");
obj.checked = false;
   }
}