How to reach the IAP ?

IAP is located at 98 bis, boulevard Arago, in the 14th "arrondissement", very close to Place Denfert-Rochereau and the Denfert-Rochereau metro lines 4, 6, and RER-B (suburban) stations.
From Means Duration  Frequency  Cost
Charles de Gaulle Airport RER B
direct to Denfert-Rochereau 
45 min 15 min 7.85€
Taxi 40 min - 1h20 30 sec ~50€
Orly Airport OrlyBus 
direct to Denfert-Rochereau 
20-40 min 30 min 5.8€
change at Antony to RER B
30 min 4-7 min 8.85€
Taxi 20-40min 30 sec ~21€
Gare de Lyon (TGV from Switzerland, Italy or Riviera) RER A
change at Châtelet-Les Halles
to RER B
17 min 5 min 1.4€
Taxi 15-30 min 30 sec ~7 €
Gare du Nord  (TGV from London or Brussels) RER B
direct to Denfert-Rochereau
11 min 5 min 1.4€
Taxi 20-40 min 30 sec ~9€
Gare de l'Est (train from Germany) Metro line 4
direction Porte d'Orléans
direct to Denfert-Rochereau
25 min 3 min 1.4€
Taxi 20-40 min 30 sec ~9€
Gare Montparnasse Metro line 6
direction Nation
direct to Denfert-Rochereau
10 min 3 min 1.4€
Taxi 10-20min 30 sec. ~5€

Taking the Metro (Denfert Rochereau station):

Here are two maps of Paris metro: interactive (seeking for route or stations, estimated time, station index) or detailed.

From "Place Denfert Rochereau":

Here is a map of the district (click on it for a bigger version).