BOZ doc typo fixes

Fix typos in doc

doc/howtos.rst

@@ -107,8 +107,8 @@ actual sample. The result is a JSON file that contains the flat field and
 non-linearity correction as well as the parameters used for their determination
 such that this can be reproduced and investigated in case of issues. The
 determination of the flat field correction is rather quick, few minutes and is
-the most important correction for the change in XAS computed from the 1st and
-1st order. For quick correction of the online preview one can bypass the
+the most important correction for the change in XAS computed from the -1st and
++1st order. For quick correction of the online preview one can bypass the
 non-linearity calculation by taking the JSON file as soon as it appears.
 The determination of the non-linearity correction is a lot longer and can take
 some 2 to 8 hours depending on the number of pulses in the
@@ -123,7 +123,7 @@ the DSSC gain in photon per bin. The proposal run number is defined inside the
 script file.
 
 The second notebook 
-:doc:`BOZ analysis part I.b Correction validation <BOZ analysis part I.a Correction validation>` can be used to check how well the calculated correction still
+:doc:`BOZ analysis part I.b Correction validation <BOZ analysis part I.b Correction validation>` can be used to check how well the calculated correction still
 work on a characterization run recorded later, i.e. on 3 broken membrane or empty membranes.
 
 The third notebook