The existence and properties of gases adsorbed within interstitial   channels of nanotube bundles
  We analyze the relationship between our group's results and those of three recent papers about gases in interstitial channels within nanotube bundles. In particular, we explain the relation between our prediction about bundle dilation upon interstitial adsorption (questioned in some way in these works) and their results. 
M. Mercedes Calbi, Flavio Toigo, and Milton W. Cole