Combine graham cracker crumbs and butter, mixing well.
Press into bottom and up sides of a buttered 8-inch spring-form pan, set aside.
Beat cream cheese at medium speed of an electric mixer until light and fluffy.
Gradually add sugar and flour, mixing well.
Add eggs, one at a time, beating well after each addition.
Add milk, orange and lemon rind, and salt, mix well.
Spoon into prepared pan, bake at 375° for 15 minutes.
Reduce oven temperature to 300°, bake 1 hour.
Turn off oven, allow cheesecake to cool in oven 30 minutes.
Let cool to room temperature, refrigerate 8 hours.
Carefully remove sides of springform pan, spread top with whipped cream, and sprinkle with chocolate shavings.
Garnish serving plate with mint leaves and orange wedges, if desired.