# some Orlik-Raymond circle bundles over orbifolds

and are surface-bundles over the circle too. These are the first examples

$\bullet$

$S^2\stackrel{\sim}\times S^1=\{0;(Oo,0,0,1);(1,0)\}$
$=\{0;(Oo,0,0,1);(a_1,b_1)\}$ with $a_1$ odd
$\qquad=\{1;(NnI,1,0,0);(1,0)\}$

$\bullet$

$N_1\times S^1=\{0;(NnI,1,0,0);(1,0)\}$
$\qquad=\{0;(Oo,0,0,1);(a_1,b_1)\}$ with $a_1$ even

$\bullet$

$N_2\times S^1=\{0;(Oo,0,0,2);(1,0)\}$

$\bullet$

$N_2\times_t S^1=\{0;(NnI,1,0,2);(1,0)\}$

$\bullet$

$N_2\times_{ty} S^1=\{0;(On,1,0,1);(1,0)\}$

$\bullet$

$N_3\times_{-1} S^1=\{0;(On,2,0,1);(1,0)\}$